Generalizing rules into rough effect categories rather than specifically saying, thats a laser, that effects this type of armor- that keeps it really flexible- but you do need scissor, paper, rock things to make strategy work to some degree. The real test is making a game where you don't just match tank killers to tanks, heroes to heroes the run at each other untilthe dice tell you who won on points. Yawn.
Lots and lots of abilities makes for a game that is not tournament friendly and hard to playtest- too few and you get hott.
I like to be able to glance at a model and say, oh yeah- that's the guy who can tear through bulkheads- that's the forcefield guy, and those guys are cowards. A few things each.