... the Eye of the Beholder trilogy? The middle one of those (The Legend of Darkmoon) was the one game that gave me as much enjoyment initially as MM3. It's a much more linear game, though. IMO its only drawback is that there's not nearly as much randomness in it. The same goodies are always in the same places, so it doesn't have nearly as much replayability as the MM games. But having said that, it's still a cracking game.
Also, if you play the first game, you can import your party into the second game with all its goodies, and then take that party into the third game. And the games are still enjoyable even with very strong parties.