You say it's a low barrier, build something and try and promote it. The worst that can happen is it fails and you 'nuke the site from orbit'. You already have

You say it's a low barrier, build something and try and promote it. The worst that can happen is it fails and you 'nuke the site from orbit'. You already have a bunch of forums on which you can promote it. You also have a list of companies that might be persuaded to pay you, or buy you out. If they can easily write this software themselves, and bypass you, then maybe you're right to be scared, and you really don't have much. It's hard to be any more specific with this vague a question. Good luck though!