Sounds like a great idea but I don't have a head for aesthetics. I made you an admin in case there's anything you want to try out but can't due to rights-lack. I do check Special:Log/delete now and then so hopefully don't remove anything but spam ;)
No? According to the article Watermaiden made about it in w:c:AnimeBaths:SAO there is one in the ninth volume of the light novel series, one in the "Aria in the Starless Night" manga, a clothed bathing shot at the end of episode 6, off-screen scenes in episode 15, and then a furo bath in episode 18. Plus one in ep 4 of 'offline' and some shots in "Infinity Moment" and merchandise.
TBH I have no idea how WM manages to be so thorough about everything, must have a lot of good sources since regularly admits to not seeing many of the things.
I'm hoping that by the time I get around to watching it I'll forget a lot of the details so that things will be surprising. Heck I've already forgotten the numbers and the galleries, no problem there.