DrNeroCF It's good to hear that iOS should be easier.
Steam Cloud works well for me. A small number of users have mentioned they lost data, but usually only after getting a new PC, or some drastic change like that. My games also have a "Save to text file" backup system that players can use, just in case. I didn't do anything fancy when implementing cloud saving, I just ticked the box in the Steam console to backup all *.meow save files in the installation folder.
From Adobe's performance optimization doc I read, and what I heard form some other guys, GPU mode does seem to tessellate vector graphics. But I'm not an expert.