There really doesn't need to be a "request" system or board. What it needs is a proper, searchable database that lists everything relevant on Patreon or wherever with a timestamp of the last update on the page and/or a checkbox indicating whether or not it's on here.
Requests are stupid. If a new user pops up on Patreon, I'm not really the one that wants to "request" it if I don't want the content. I just want everyone here to know who the fuck the user EVEN IS. You can't search Patreon reliably for anything, because the search is trash, just like here where the search function is abysmally trash, but only slightly better.