I think most western cartoons, TV series-wise, fall into "action", "slice of life" and "comedy". Anyway, off the top of my head, some sci-fi cartoons include :
Bounty Hamster
Wander Over Yonder
Invader Zim
My Life as a Teenaged Robot (I guess? I only saw the first ep)
and
Aeon Flux, which I haven't watched, but is probably the kind of cartoon you're looking for.
And also, some parts of Adventure Time, mainly Deep Purple, Pre-boot, Re-boot and Islands (the miniseries)
