Some random Baths-related thoughts.
It doesn't make sense that creatures as markedly prudish as dwarves should be perfectly willing to just strip down and bathe themselves in front of anyone & everyone who might be around to see. (And if they don't strip down, that doesn't make sense either.) Traits like Decorum and Bashful should affect how a dwarf feels about bathing when others are in his/her line of sight, probably with a modifier if it's anyone of the opposite sex.
Just as doors can be flagged as Passable / Pet-passable, wells should have two flags: One that allows/forbids drinking, and one that allows/forbids bathing. So you don't have to get a drink while standing in the blood that somebody else just washed off, and people taking a bath don't have to worry about somebody wandering in for a drink. Creatures that are close to death from dehydration will ignore the Drinking flag.
There should be two new traffic designations: One that applies the "Forbidden" pathing cost to male creatures only, and another that similarly discourages females. Invaders should ignore these, of course.
Water that contains no mud, poured onto a surface that is void of sand/soil, should not create mud. This would allow the creation of clean swimming and bathing pools.
I'm sure the furniture item of Bathing Tubs, and allowing Wood Furnaces & the like to warm water, have been mentioned before.
Dwarves that change into clean clothes after their bath should receive an augmented happy thought for doing so.