I like the Isaan places and they're always pleasantly cheap and uncrowded compared to Bangkok, but the summer months there can be really oppressively hot & humid. Like July in central Florida. It's much better in "winter" when lows can be in the 60s, Thais are wearing jackets at night and I still have shorts on.

Pattaya has gotten so heavily visited, especially by Chinese (and Russians before Vlad's economy dipped) and other nationalities that the "traditional" western visitor is losing share and getting turfed out. Walking Street gets lots of gawkers and even some tour groups ("follow the flag!"), but as in Las Vegas on Fremont Street, it's become outdoor and street-focused, with many people never going indoors anywhere. Also lots of discos.