Farscape is like some weird amalgam of Firefly, Red Dwarf and Blake's 7. It's a fantastic show that I ordinarily wouldn't be able to recommend highly enough.
Given a 'that or Babylon 5' though, it would always have to be Babylon 5. B5's just that
good. It's probably the only
show that I'd rank higher than DS9 in the genre.
Its first season, on first glance, could be construed as hit and miss, and to be fair, there are some absolute stinkers of episodes in there. However, even those usually include a few nuggets of pivotal information that will be revealed later in the season, or sometimes even much later in the show's lifespan.
Seasons 2-4 are IMO, some of the best the genre's ever produced.