But probably the best option if $500 is top of budget?
I have always loved home theater but only recently had the space/resources to upgrade beyond bargain basement sort of stuff, so I think I understand where you are coming from. One important thing that I have learned is that, especially for movies, upgrading your subwoofer is maybe the most noticeable thing you can do,
and it is relatively inexpensive to get a really good sub as compared to upgrading every single one of your speakers. I would take the time as necessary and save for at least an SVS PB-2000 or PC-2000. The difference between that level of quality and what is beneath it is pretty remarkable for the price, at least in my experience. (I can't speak as much to the
next level of quality, as I have never gotten much of a chance to try anything beyond that relative price-range.)