I think you are very alone with that opinion. 2 was just a weak sequel, using the same assets and the same town. 3 actually improved the game and 4 turned it into a superhero game. 2 is by far the one with the least amount of effort put into it.
you are so wrong on all accounts. 2 was the best sequel in the series. 3 featured an uninspired town with a story littered with sex jokes. I mean come on, they used a cut activity from 2 called guardian angels as a main story mission twice and you call SR2 lazy? pfft. and 4 was so different it might as well have been a different game.