If your holiday will involve going to bars and offing boys, Bangkok could end up costing you twice as much as Pattaya - and believe me, you're not going to get any more for your money than you would in Pattaya.
Pattaya is much less commercial...more lack back in-and-around the gay venues...a bit more sleaze (just the way I like it)...with an ocean.
I enjoy short trips (2-3 nights) to Bangkok, but that's the limit.
I love Pattaya...always have.