Ooh that is an interesting focus, I personally love sharing and reading about startup ideas and can't get enough of that content online.

In case it's interesting, along this direction there's halfbakery, pg's essay on how to find startup ideas, YC's RFS posts, and more recently the Startup Ideas podcast/youtube channel which features guests sharing ideas they've been thinking about.

Edit: I see you updated the site with example problems, those are great. I could see this being a great structure for collective solution ideation.