Here's an update for list of games to get on X1 for easy gamerscore.
Three Fourths Home: Extended Edition (ABSOLUTE SHIT. THIS IS AS MUCH A GAME AS AUDIBLE AUDIO BOOKS)
Another World - 20th Anniversary Edition You can speed run this in about an hour and a half
Nutjitsu Longer than when it first launched but still about 8 hours
Funk of Titans terrible game again
Sixty Second Shooter Prime gotta be a bit good
Goat Simulator flappy bird is a bitch, easy otherwise.
Duck Dynasty showing gamefly because you don't want to pay anywhere near full price for this. or own it. You don't even need to finish the game!
#IDARB in about an hour if you have a kinect
Castle Crashers Remastered easiest if you played it before on X1
Max: The Curse of Brotherhood most time consuming but easy.