2 is definitely the overall better film because instead of Kevin being a jerk to his family for the first half of the movie, which makes him out to be more of a brat than a sympathetic child hero, it places him alone in New York amongst strangers and establishes that Tim Curry and Rob Schneider’s characters are a$$holes off the rip so you root for Kevin to outsmart them and then when Marv and Harry show up its business as usual.
Kevin is easier to root for in part 2 than part 1. Plus Macauley Culkin’s comedic timing and delivery were on POINT.