An RPG game would keep me absorbed for a while if I could get into one. I use to be really into FPS, but ever since I quit playing BF I haven't found one of those that hold my attention either.
There really isn't any good free rpg's out there that continue to keep my interest.
Path of Exile is pretty good if you're into top down dungeon runners like Diablo.
But I would suggest picking up Divinity on Steam. Right now it's still 60.00 but if it ever goes on sale grab that shit.
Great game all around, if you ever played any of the Forgotten Realms/ Baldur's Gate series you'll love that game.
I know Steam has a bunch of recent f2p releases, might want to check them out and cycle through some user reviews to weed out whats good.