It's hard to beat the aesthetics of a miniature game, but it's hard to beat the awesomeness of wargames. There has to be a nice middle point, but I've been burned by minis games that are too expensive and too simple.
I have looked into sci-fi starship games though, those look like they could be a blast. Sci-Fi doesn't need to be that deep to fun, sometimes. Although I want to avoid a fist-o-dice mechanic like Warhammer 40k.