I recall a similar thread like this being locked awhile ago, I think it was about Hanenbow.
Oh well, this one seems to be taken more seriously.
I've always thought of New Pork City to be for casual Brawls, I'll admit, I do like it because it's not your average stage. There are plenty of glitches to discover, and it's great practice for aiming your projectiles, or practicing flying.
Despite people not liking this stage, it still deserves to be there, but I think we can all agree that Fourside would've been the better of the two stages to be in Brawl.