I don't really like running SM in 16:10 (my monitor's ratio) as nothing is made with it in mind. BGs, videos, themes, etc. are made in 4:3 or 16:9. So I prefer to run SM in 16:9. The only problem is that I can only do this by changing the resolution as just changing the aspect ratio just renders a narrower/wider picture and compresses/expands it to fit the resolution. And even changing the resolution is buggy for me; 720p is too wide. I tried 1440x810 but SM decided it didn't like that resolution. I've found that 1366x768 works fine, but it's slightly blurry. It would be easier for me to just change the aspect ratio though.
Also, this might be related (might be because my desktop and SM resolutions are not equal) but whenever I Alt+Tab out of SM and go back in, part of the picture is missing.