This is looking good! I like the style.
There are a few things I'd like to suggest to get rid of some of the 'offness'.
The clock. Normally a clock face is flat and the surrounding frame is bevelled. The way you've shaded the bottom-right of the clock face makes it look like the face is rounded. If something's flat, I think it's often a good idea to keep it the same shade throughout (except for reflections like you have on the floor, or shadows where appropriate, of course.)
The panels. The top ones are casting a shadow over the next ones down, and so on. So looking at those, I think the top ones should be sticking out further into the room. However, the shadows on the sides are all the same, so that makes them all seem to be the same distance from the wall. This dissonance feels a little off to me.
The bed looks like it's floating. The reflection probably needs to be handled differently, I'll get back to you on that one.
The other furniture in the room doesn't reflect.
As a matter of taste, I'd prefer if the crossed window reflection was anti-aliased, or if it was straight on. But that really is a taste thing.
The character has a dark outline and a shadow. Everything else has light outlines and reflections.
These should all be easy things to experiment with, to see if you can make it feel more cohesive.
Edit:
If you want to make reflections part of the style, chat to whoever is developing this (or if that's you, chat to yourself) about how they'll need to be implemented and if that impacts on what's possible in the artistic style.