I love that series. The fun thing to do with it is to start with a thief in QFG 1, with at least 5% in every skill, and work every skill up to 100%, switch over to a paladin at the end of QFG 2 after working every skill up to 200 (which means that, yeah, you can't do all the thief quests, but you don't want to be a thief for QFG 3, because there are not good thief subplots in 3), and continue like that all the way through.

I managed to get all skills up to 500 at the end of QFG 5, and end as head of the Thieves' Guild and be offered the throne (which I gave up to Elsa).

For a while, I sketched out an outline for a QFG 6 that I tried to write as a fan-project, but that never went anywhere.