My first thought would be to go with 4.0 or 4.1... floorstanders for the front, compatible bookshelves for the surrounds, phantom center (as long as your receiver will split the center channel between the mains) and see how that works. You can get small center speakers but I expect they're going to sound... small.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8