1 or 2 seasons?
Well that's no likely - in terms of cost and ect. -, moreover I think it could ruin the entire feel of the show.
Ruin? Why ruin when we have more screen time?
Becasue we have more screen-time, that has to be filled, and series tend to end up with budget cut downs and would end up with themes and events that could get really repetative.
The series could be good for a very in-depth chronology, but would demand very keen viewers.
If it were a series I would limit it to a single season - and as much as 26 episodes - and least around 13. IMHO coming from watching several shows, that's the lenght a good show can deal with, without being too drawn out or cut short.
However I'm more inclined to a mini-series around 3-4 episodes, each one a little bit more than an hour, maybe 1.5 hours.
That way it would have enough screen time to go in-depht, avoinding the shallow story trap of Wing-Commander Movie but still assure a very high quality product.
I had a thougt thou...how about making an animated film?
No, please don't think of anime with leasurly dressed big-eyed chicks and huge...well do think of anime, but substract the later stuff.
If the whole thing was animated, then all the space-scenes could be easier recreated, and the show won't have to suffer from the usual space-flick genre sinkness - like shaking camera, identical looking rooms, for simply the sake of budget.
Huge scenes, detailed battles and very good, dynamic camera motion could be used.
That backed up with a very realistic character design - think of smg. like Ghost in the Shell, or Jin-Roh - with exquisite shading and brave use of collors could create a memorable visial appearance.