1. The Wet Sticky Bandits actually have a REASON to relentlessly battle a child
The motivation of the Wet Bandits, Harry and Marv, in Home Alone 1 is pretty suspect. Harry just really likes the McCallister house, and has always dreamed about robbing it. That's it. That's why the two pursue a desperate and relentless home invasion, despite knowing that there's a kid inside AND (after their initial attempts at entering) that he's wired the whole house with devious and painful booby traps that they are woefully unprepared for. The instant they found out a kid was home, they should have written this off as a bad idea and moved on to another house. Why risk the kid calling the cops, or the ethics of potentially having to ASSAULT A CHILD (let alone the added criminal charges that would be added in addition to simple robbery). Basically, it's not worth it.
But in Home Alone 2, it makes sense why they're doing battle with a child. Not only does Kevin have evidence implicating them in the toy store robbery (although honestly that shouldn't be a big concern - they're ALREADY wanted fugitives for escaping jail, all the photo really does is give the police an idea of their current whereabouts), but on a more basic level, they just want revenge on the kid who embarrassingly stomped their butts last year. That's the kind of emotion-based storytelling that can excuse them soldiering on, despite the obvious physical peril they're risking. It makes them more compelling villains, because we have a good sense of why they're doing what they're doing.
2. The plot actually makes some semblance of sense
The plot to Home Alone 1 is simple but surprisingly full of holes. Why wouldn't the police try A LITTLE HARDER to determine whether Kevin was still in the house or not? Why wouldn't they put out fliers and/or an APB in the area - especially given the number of neighbors and townspeople who come into contact with Kevin throughout the film? Why wouldn't the parents ask a neighbor or family friend to check in? There's the thin reasoning for why Kevin didn't just call the police (he's worried he'll get in trouble for accidentally stealing the toothbrush), but by the time he realizes armed criminals are plotting to break into his house, Kevin's a smart enough kid that he should have just given in and called the cops.
But in 2, pretty much all of these issues are dealt with - of course the parents and cops have a hard time tracking Kevin down: at first they have no idea WHERE he is, period. Eventually, they figure out he's in New York City - the most densely-populated city in the United States, where they have no friends and their only relatives are out of the country. In the first film, it should have been glaringly obvious he was in the family home (where else is an abandoned 8 year old gonna go?), but in the 2nd film, it makes sense no one would really know where to look for him. And as for why Kevin didn't call the cops - he committed CREDIT CARD FRAUD. That's a pretty good reason to steer clear of the police.
3. The Talkboy is dope
This is less of a good plot/storytelling reason and more of a "this was some genius-level marketing / product-integration and I gotta tip my hat to it." The Talkboy is a very basic thing - it's a tape recorder with some sorta simple features (like vocal slowdown). But making it into a handheld toy used by a lovable scamp to defraud a major hotel and prank snooty British concierges made it SUCH a compelling product (especially given Kevin's insane ability to instantly fastforward and rewind the tape to the EXACT spot he needed for any given situation).
4. A pleasant reminder of a pre-9/11 world where kids could just hop on whatever plane they felt like without parental supervision and it was no big deal
The early airport sequence seems particularly laughable in our security theater-ridden post-9/11 world, where air travel has become a much more cumbersome and logistically-frustrating nightmare. The idea a kid could wander onto a flight with no parental supervision OR EVEN A TICKET FOR THAT FLIGHT and everyone would just be cool with it is astounding. Simpler times.
But it also deals with the idea that - as bad as these parents are (and they ARE genuinely horrible parents), at least they remembered to take their kid to the f***ing airport this time.
5. The idea that parents could accidentally lose one of their kids on Christmas two years in a row is darkly hilarious
On that point though, this (sorta lazy) plotpoint makes for a completely hilarious situation where the parents have inadvertently abandoned the SAME CHILD two years in a row on Christmas. For movies predicated on how strong the bond between the mother and her son truly is, it not only completely invalidates the previous film's heartwarming finale, but it really brings into question how social services hasn't gotten heavily involved in the lives of the McCallister parents. This might sound like a knock against Home Alone 2, but I promise it isn't: it hints at a weird, dissonant darkness that was always simmering in the first film, with a kid who revels in the torture of two grown men and who nearly has his fingers EATEN by one of the torture victims. Speaking of...
6. Joe Pesci doesn't try to eat a child's fingers
Listen, I like some implied darkness in my kids' films (I'm reminded a lot of Jumanji) but when it's made as overt as Joe Pesci sticking a child's fingers in his mouth and right about to bite down, that's a bit much. I'm okay with the Wet Bandits wanting revenge against the kid who had just been tormenting them, but to literally attempt to actually eat his fingers is the kind of messed up thing I'd expect from Ramsay Bolton, not a PG John Hughes movie.
7. Pigeon Lady is way better than Shovel Grandpa
Shovel Grandpa (aka "Old Man Marley") is fine as the mysterious, old, sad mentor who talks to Kevin about his life's problems and puts them into perspective with their own tale of tragedy. He has a strained relationship with his son and shovels a lot and he stops Joe Pesci from eating a child's fingers, so I'll always appreciate him for that. But Pigeon Lady is way better.
For one, she commands a creepy army of pigeons, which is badass. Anyone who has firm command over something out of an Alfred Hitchcock movie is a-okay in my book. But moreso, the relationship dynamics between Kevin and the film's respective Old Person Who Saves the Day In The End is much more interesting with Pigeon Lady. Shovel Grandpa's arc is that he and his son don't talk because they had a fight, and then they reconnect and everything's fine again. He doesn't need Kevin for any reason other than as a gentle push to make that reconnection. But Pigeon Lady doesn't have such a simple fix - she's homeless, a heartbreak early in her life has left her socially-broken and unable to connect with anyone, and her only "friends" are her Murder-Pigeons.
What Kevin represents to her is something much more meaningful - someone she can speak to (she apparently hasn't spoken to another person in years) who won't reject her, likely because they're such kindred spirits. Kevin also has an anti-social streak to him, so when he really listens to her and converses with her, it's a major emotional step for the Pigeon Lady. But finally, in the end, when he offers her one of his two turtle doves - symbols of friendship and love - it's big. They've both done something hugely important for one another - she saved his life, and he gave her something she could trust.
Still, woulda been nice if Kevin had offered her some cash or food or a warm place to sleep for the night (seriously, the McCallisters are rich as hell AND they just got an assload of free presents that they don't need at all - help out Pigeon Lady a little more).
8. Tim Curry is hilarious and great
Here's the great thing about Tim Curry in Home Alone 2 - he's an antagonist because Kevin is our point-of-view character, but he's completely justified in his actions and suspicions. Also, literally every face he makes is an inspired piece of art, like the Cheshire Cat had a baby with Nigel Farage.
The sheer glee and deviousness Tim Curry approaches the task of a hotel concierge trying to deduce whether or not the hotel's been scammed by a 9-year old is amazing.
Plus, every line and reaction during the 'Angels With Filthy Souls' scene is incredible (particularly mouthing "Snuffy?" and his enthusiastic "I LOVE YOU!"):
And not only that, but I genuinely believe that Tim Curry is the only actor on this earth who could make us believe a character thought this was a real human being:
9. The traps are SO MUCH BETTER
The idea that Kevin McCallister is a sadistic sociopath with more in common than Jigsaw from the Saw films than an average 9 year old is not a new argument, but it's so well-represented in this film that it takes it to a whole new level. Kevin's traps in the first film were a childish matter of necessity - the thieves were coming to HIS house, and in the absence of his parents, it was HIS job to protect it. And while he was pretty accurately predicting what the thieves' next moves would be, it never got too outlandish.
Things are different in 2 - he leads the Sticky Bandits to relative's slightly abandoned home, one he has no emotional attachment to, for the sole purpose of tormenting the thieves. Again, not STOPPING them, but to mercilessly torture them in increasingly elaborate ways. He understands the two will know to dodge the first two paint cans hurled down the stairs, so he includes a giant pipe that they won't be expecting. He knows the plumbing is off so when Joe Pesci's head is set aflame, he'll attempt to douse the first in the toilet bowl, so he fills it with FUCKING GASOLINE. And he knows the chase will eventually lead to the rope attached to the roof of the building - but instead of lighting it on fire the instant he gets to the ground so they can't follow, he specifically waits until they're halfway down so they'll be left with the horrifying choice between being terribly burnt or falling 4 stories.
Also, the pranks start with Kevin HURLING BRICKS AT MARV'S FACE, which is a notable step up from using a BB gun.
It's some next-level shit, but added on top of the fact that it was wholly unnecessary in the first place makes it the exact right kind of dark undertone that the Home Alone series was all about.
10. Kevin doesn't revel in the idea that he's essentially murdered his entire family in this one
Again, on the topic of undertones - Home Alone 1 pushes the basic premise into far too dark territory right off the bat by having Kevin actually think that he has somehow willed his ENTIRE FAMILY into non-existence through his disdain for them...and loves it. He's so happy that his entire family is (for all intents and purposes) dead, that his excitement comes across a lot creepier than I imagine the filmmakers intended.
The whole schtick of the premise was intended to be a kid livin' it up and doin' all the stuff that he's always wanted to do when left (wait for it) home alone. But to undercut it with the fact that he's only able to do whatever he wants because he thinks he killed his family with a wish pushes things WAY too far into a creepy abyss. Luckily, Home Alone 2 addresses this issue a lot more gracefully.
Kevin knows EXACTLY what's happened the instant he arrives in New York - he got on the wrong plane, his family is in Florida (where there's heat and palm trees and his crummy family), and he's in New York (where there are Christmas trees and snow and NO FAMILY). And he decides he's gonna take advantage of the situation and live it up, as any 9 year old kid left on their own in one of the most exciting cities in the world would do if given the opportunity. Eat ice cream and watch grown-up movies in the basement? Psssh please. He's doin' that BUT IN THE FRIGGIN' PLAZA HOTEL (and having everything brought to him by Rob Schneider). A large cheese pizza just for him? Whatever - compare that to a large cheese pizza AND A LIMO TAKIN' HIM TO A CRAZY-GREAT TOY STORE.
Basically, Home Alone 2 delivers on the promise of "a kid livin' out their fantasy" a lot better than 1, and with less of a creep-factor involved.
But, again, yeah - mostly the "no Joe Pesci trying to eat a kid's fingers" thing. That's what really makes Home Alone 2 the superior film.