One last clue about the direction a sequel would take (mods please forgive me for posting four times in a row):
Over the last few years reports have been circulating about a new big budget version to be made by the BBC with Paul Darrow as the only surviving member of the crew from the original show. Before he died Terry Nation wrote a plotline involving a young rebel calling himself Blake rescuing Avon and Villa from a federation colony. Life is good for our favorite misfits; they have every comfort in exchange for a few pro federation statements. As you can imagine they are none too pleased at being rescued and whipped halfway across the universe so the adventure begins again. This idea may have died with the shows creator in 1997, but only time will tell.
Interestingly, we seem to know a lot more about the hypothetical Blake's 7 sequel than we do about Star Trek 2013 at this stage. :-)