if you designate a room everything inside the room designation belongs to the assigned dwarf, right? even the door?
or at least they can admire it and have happy thoughts?
What about floor hatches?? If they are inside the room (as in on a floor tile that belongs to the room designation) they behave like a door in the wall in terms of ownership and thoughts??
What if the hatch is in the ceiling? Like inside the room there is an up-stair and the down-stair in the upper z-level has a hatch, does that hatch belong to the room??
Every furniture inside a room belongs to its owner, yes. Including floor hatches on the ground, but not on the z-level above. Statues and windows too, but they remove floor space and the associated value, and sometimes some wall tiles (like in a corner). I've had a mayor's room with less value after adding exceptionnal quality clear glass windows as a middle separation.
Doors not set as internal are NOT considered as furniture and do NOT give value to a room. My only doors set as internal are in noble's rooms, if I separate their bedroom into 2-3 separate areas. Oh, and between my dining room and my wells room.
As for good thoughts, for me they are pretty random. Any furniture can generate them...