GundamFan, I have to ask, did you secretly watch Space 1999 because you wanted to play with the toys?
.
That being said, if you liked
Space 1999 for its storylines and characters, I would like to offer up
Blakes 7. Created by Terry Nation (best known as the creator of the Daleks), this extremely pessimistic sci-fi features a band of rebels fighting (and often losing) against a dystopian galactic federation. While the special effects are generally quite terrible, and the costumes not much better, the characters are very interesting and the entire series is shrouded in complex moral ambiguity.