Our real problem with Twilight Imperium is there's a lot you can do. We have a couple of players with option paralysis, so each round of turns goes like "2 minutes, 4 minutes, 3 minutes, 40 minutes, 2 minutes, 30 minutes". Makes the whole game take about twelve hours - four players don't enjoy it since they spend 95% of their time waiting, and the two OP players get really upset if they're "rushed" and don't enjoy it.
It seems to combine the "game is over for you if you messed up the first couple of turns, but you'll be playing it for a long time yet" aspect of Settlers of Catan, with the interminable dice rolling combat of Risk. If that combination, but slowly, sounds perfect to you, then it might be your new favourite game. To me, there are much more fun games that you could fit into the same timescale.