didn't like alpha centauri that much, once i realized i couldn't make the healing paradroping APC design to work. also felt it was just a weaker civ clone
colonization was the first game that really addicted me. would love to see a sequel with current graphics, but the time period limits how much could be added to it
master of magic badly needs a sequel. the game was a masterpiece. and i don't really mind that it was not balanced, that made it more exciting. i've played all 4 original games in the poll, and master of magic was the best - even better than civ 1. if you've never played it, you can find it on one of those abandonware sites. too bad an old system with high DOS compatibility is usually needed to play it properly
MOO 1 and 2 were excellent, but MOO 3 was, to put it elegantly, a piece of droppings. it left a bad taste in my mouth, and i'm no longer eager to see MOO 4
another TBS that deserves a sequel is Xcom. forget the crappy FPS spinoffs, a true Xcom 4 would be sweet