True. I usually wait for the trade paperback collection of those things, though.
Best thing would be to either play the multiplayer. Or, start a new game but try things different. On parts where you sneaked try just avoiding everyone at all, or go guns blazing. This way the game stays different. Trust me, the game will do new awesome things if you just play a part differently.
Play it again, my friend. It is likely you missed at least some of Ellie's jokes, optional conversations or such. They alone are almost a reason to play it again...
Believe me, the feeling of first playthrough won't decrease if you play a second one, I've nearly played 7 times through and still thoroughly enjoy the gem... I meant game. It is the only campaign/single player game I've played this many times a little over a month while still liking it or having a reason to play it other than mere Trophies.