Originally Posted by Cormac 
Because it's a great rpg.
That's why I'm replaying now - I might debate the rpg-ishness of it, but not the greatness.
Interestingly, restarting a new game with the Knights of the Nine (which also puts the other 6 or 7 mods on as well) shows new weaknesses - basically they were designed to be added one at a time after you'd been playing for a bit.