We can recommend the couples massage at Bali Hai. Lots of fun for all.... We liked the service at the Bali Hai on Sawwatdirak, but there are other locations as well. Also there are plenty of very "couple friendly" bar girls to be found, just make sure your hotel is guest friendly, or has reasonable joiners fees. Some of the more family oriented hotels are decidedly guest un-friendly. Also if you have somebody to keep an eye on the kids, and wish to sample the BG scene there are plenty of short time rooms available in Patong for "encounters" of the nighttime sort.
Enjoy,
The Easy's