Documentation would be a HUGE help to the code quality of OpenSSL because someone would have to actually sit down and describe its ghastly interface. Whoever it was would get about half way through it and then stop and say "Wait, what? Seriously?"
The only other codebase I've seen that's remotely as hairy as OpenSSL is GCC's gnarly mess. (I've heard it's improved since I looked a few years ago.) And that's notoriously engineered to be difficult as possible to contribute without giving back; I can't imagine what OpenSSL's excuse is. Any sane programmer would have cold sweats even if they understood the implementation because it's so difficult to figure out and verify what the fuck is going on internally with any speed.
Documentation would help, but a good cleanup would make provided documentation much less necessary. Crypto may be difficult to understand, but with clean coding practices and formal verification (even on an audit workflow level) would be a much better investment, IMHO.
The last thing OpenBSD or OpenSSL needs is a whack of totally-useless js on their website.