Fox has a bad habit of airing episodes of cool new shows out of order and weeks or even months apart, then being surprised when they don't live up to ratings expectations and cancelling them.
Firefly, being a scifi show, does rely a bit on being able to establish its universe and as well also needs to establish its characters due to its dramatic elements. Not airing the first episode of the show until dead last and airing other episodes in odd timeslots out of order did it no favors.
The concept had meat enough for another few seasons at least, and if it hadn't been treated so poorly, I think it could have been fairly sucessful. It's not ahead of its time, it just never got a chance to build a fan following while it was on air due to being handled incredibly poorly by Fox.