Looking good, mabte...some houseplants and some books in the shevles? ;)

Maybe generic posters of bands? Or a bookshelf? Looks nice though.

Nothing on the floor?

Has to have at least one lone sock making for the door to roam fee.

A couple more turd posters just for the aesthetics, maybe a hang in there one too for good measure.

If anything, a chair or two, maybe a bean bag or something to relax in. Probably some clutter in/on the shelves to make them less empty, and to make it look more 'lived' in. Other than that, just random clutter would also suffice, not necessarily stuff on the ground, but possibly stuff on the dressers and such.

This might seem like a weird suggestion, but a pole maybe? I get somewhat of a tomboyish feel to this room.

Naked girls.

The shelves look a tad bare, anyone with a serious need for hittin a bag in their room is going to have protein powder somewhere, music player(s) and magazines with tips/tricks.

That's really I can think of. Otherwise, I'd want this room!

Good job with the mirrors, that is a cool effect. other than that I'd suggest some gloves or wraps to go with that bag, maybe a gym bag on one of the shelves. Depending on if its a human or furry room and depending on plantigrade or digitigrade feet, there might be a spare set of gym shoes or running shoes. The vat/box/tub of protein powder or supplements is a good suggestion too. Only other thing I can think of is maybe to slow it down a bit, its hard to study the room itself with it moving so fast, well... it is hard for me at least.