I would like to see a little bath cabin in the house(s) similar to the change rooms in the spa and GI (even if the GI change room doesn't work for the player yet). It hasn't to be a room to enter, than just a door to go through and instantly come out changed. The mechanic could be the same as with dolls: click/enter and be changed!
When the player does not use the bath before going to bed, there could be a small energy cut because of bad sleep.
Something like that...