Despite the long lists of sci-fi and pseudo-sci-fi shows that a couple of posters have just supplied, I agree with the OP's general sense that there isn't anything that really ticks the box just now.
What I mean by "ticks the box" is something that stretches your mind, that posits an environment seemingly without limitations that can encompass micro-scale character development plots and in the next episode, take you to the brink of a credible
end-of-the-universe, no-really, the-hero-is-not-guaranteed-to-win type situation.
The only ones I can think of within the last ten years (just) that did that were Farscape and Firefly.
I liked Trek (obviously) but we're all thoroughly over-dosed on it now. Time for a crash diet... thank you JJ Abrams for providing the motivation!
I liked Stargate (except for any episode with Jonas in it). Atlantis was good too because characters can be all you really need sometimes, but it aged much quicker than its parent because it wasn't doing anything new. Universe has just lost my interest, which is ironic as it's exactly what I used to think Stargate should be!
I liked the first two seasons of BSG. And that was it. And if that has put some peoples noses out of joint (I'm wearing my flame retardant underwear), then you'll love this... I can't watch Caprica because it's so predictable.
Eureka - bleh. Warehouse 13, read it in books years ago.
But then, isn't that the problem now? We've seen it all before!
I'm ruined and I'm sure I'm not the only one on here who is. Most of us no doubt spent our formative years reading the classics of science fiction literature which collectively contain the very same plot lines that so many writers are busy trotting out today, then patting themselves on the back for being so clever.
Which is why I thought
Farscape and
Firefly were both such a good effort, because they regularly surprised me in a way that almost nothing else did. Sure, Farscape was intermittently absolute
dren and I watched a rerun on FX just a couple of days ago (S4: What Was Lost) that I wouldn't have wiped my arse on, but I saw another one today that I loved every minute of (The Perfect Murder), and so it always was with that show. Flashes of brilliance that were all the brighter for being contrasted with the occasional Friday night job.
And while Farscape was stretching your brain across the cosmos, Firefly was busy engaging you up to the ear lobes in a brilliantly written character-based story with more than enough action to satisfy anyone except maybe those jaded, soulless ratings-whores who run Fox.
So perhaps that's what we need to do! We need to feed Farscape a bucket full of randy molluscs, get Firefly really drunk, then lock them both in a room without access to contraception and see what
emerges...