This year, for PS4, I have enjoyed Transistor, Oddworld, MGS5, Rocket League, Lara Croft&The Temple Of Osiris, Gauntlet and King's Quest.
When you add in the games I have played for the Vita and PS3 and the extra discounts on games I have bought because I am a PS+ member then the subscription is a steal.
There are a few retail games, Diablo 3 and Lords of The Fallen, that I would play if they were on the PS+ service but I feel if I hadn't paid for them then I can't be that bothered about them.
This month coming, I will be trying out Grim Fandango and Nililumbra.