I think encores should be scrapped if that helps.
My respect for a band grows a little bit when they leave the stage the first time and the house music comes on.
And where exactly is the surprise if you know that they are going to play x album going in assuming you know the order of x album?
Nostalgia trip, sure. Surprise? Not really.
I have seen some good full album shows (Burma, Mould, Devo right off the top of my head) but throughout all those album sets, I thought "OK hurry up and finish the LP so you can play some other stuff." If you want to hear an album in full, just kick back and put it on.