This question is a two parter:
1) Which city/town would you like to live in? (Can be per Gen or your overall most fave!)
For me, my top place would be a tossup between Azalea Town or Nacrene City. Azalea is small and cosy with my favorite Gym Leader, but Nacrene City is artistic and has a museum which I just love!
For the First Gen games Lavender Town has my vote, because I'm a morbid person who loves spooky stuff, and for the 3rd Gen I pick Sootopolis City, because I love the Greek influences. Not really a fan of anyplace from GEN IV.
2) Which city/town would you most HATE to live in?
Hands down Snowpoint City. I would be freezing my a** off there.