I have to admit this is something I'm looking for. I really like the low profile cases because they tuck underneath a TV and looks like it belongs there. but they all only use low profile cards, which basically limits me to a 7750 (or a 7850 if i can actually find it).
There have been riser cards since sliced bread, so it should be fully possible to make these cases. do you know of any?
More about :low profile cases accept full height video cards
As far as cases go, a low profile case is only ment to fit low profile cards so unfortunately your best bet is to go with a 7750. For light gaming in 720p it would be a great option but just dont expect it to perform crazily awesome. Another option is purchasing a mitx or matx case as they tend to be smaller cases that fit full sized graphics cards but may not fit under your TV.