Since there are already lots of steam features I think it would be great to have option to save single-player progress.
But not actual saves. Only the progress, I mean as you complete campaign, showcases or challanges, you would have it saved forever.
Also game settings, game profiles and other stuff should be saved to steam cloud.
I really hate that idea, if I reinstall my PC and forget to back up and all of my progress would be gone.