Wonderful list! (Even though I haven't played the majority of these games, it is well-written and makes me think twice about being an almost exclusively F2P gamer)
I think that "The Stanley Parable" and "The Beginners Guide" Also deserve a spot on this list. (Or a similar list for short games) If you have never heard of them, DO NOT DO ANY RESEARCH, just buy them. (Learning about them first takes the fun out of the game... and it's a unique 1-time experience that you won't get with many... any other games).
P.S. You look exactly like a (sorta) friend of mine! Obviously a little younger, but you look scary-close alike to her.