D'oh. MicKo beat me to it.
Oh well, it might still be helpful to you.
I did basically the same thing he did, swapped the wall colors around and spruced up the place.
Your character seems like a writer to me for some reason, so I gave him a desk and chair with some writing paper for him to go to town with. He also ended up with a corkboard on his far wall, maybe he keeps important reminders pinned to it to keep him from forgetting.
I messed with the bed, because the matress being the same color as the sheets was weirding me out, and also changed around the perspective on a bunch of the objects. I also angled the roof a little to make it look a bit more roofish, and brought the doorknob, and a few other things, down some to what I thought was his level.
I edited the character himself some, too. Gave his cowlick more character and made the back of his head less square, and gave him some sleeves (he looked a little odd without them, but if it was a design choice please ignore this).
The house outside got done over, too, because as it was it looked a little like a doghouse. (the door was really small, too, how did he fit in there?)
