I also like the idea of an optional theme!
Just like the "No Comfort" jam implies, maybe the optional theme could be...the same? The character(s)/player could be placed in an awkward or strange situation, something that makes them feel uneasy. Or, the controls could even be programmed to be "uncomfortable." It's a super broad theme though. ^^;;
I guess it'd be for the creators who want top-notch awkwardness when working on their project.