Bali is a long and expensive treck for 3-4 days. I did it once which was fine, but would not do a second time. Best thing is the beauty of the island and the number of straight handsome Australian surfers.
Chiang Mai is nice but a little too sleepy.
Pattaya is a simple two hour ride by car, about 1200 BHT each way. Gay beach in Jomtiem.
Koh Samui is also a very nice beach, a little gay life. Certainly a good place to unwind and relax. Always walk the beach for dinner, dinner on a lounger with candlelight.
Siem Reap sounds good, still on my "to do" list.