Perhaps Minion Masters has elements of GoW that you would like with enough gameplay differences to feel completely different. Its in EA at $22 right now, but you can get free keys because it is going to follow (AFAIK) a very similar F2P model as GoW.
Runestone Keeper is Minesweeper on crack.
Chronicles of Emerland. Solitaire is a really fun Pyramid Solitaire even though aspects of it are really corny (skippable hidden obj game).
I second Lyya's suggestion of Divinity OS and put it personally in my top 20 RPGs. I will say, however, that they made a horrible mistake when they level-gated the first 100 hours of game. Lots and lots of trying to figure out WTF you are supposed to go with little guidance. You will die a hundred times until you figure out where you are "allowed" to go.
If you're looking for a "welfare diablo" I say Hero Siege.
If you want retro, insane arcade RTS get the original DOS Z by Bitmap Brothers (modern remake is feces)
Just a few randoms that came to mind.