I would absolutely recommend getting some high end display cases (see my Collection here), but if you can't afford that, then thin out your displayed collection and showcase some of your better figures. I had everything crammed in one very nice display case, but crammed is still crammed and it looked bad. I bought a second case and spread things out and I think they look much better now (of course I could stand for a 3rd case as I immediately filled the second one as well and still have quite a few figures living in the closet). I strongly recommend getting something w/ lights and if possible glass shelves. If you can't get lights pre-installed, then go to Lowe's and grab some under-cabinet lights and put those in recessed areas if you have them. I took a barrister's bookcase and a stereo cabinet, put lights in them and had a pretty nice display relatively cheaply.
Piggy, that is really really nice. Those lights work perfectly and your limited display really showcases what you do have out. That is awesome!!!