Your "UA Trending Feed, PoC" is very cool. I think there are better, more complete, ways to implement what you've built (I completely understand you implementation strategy though), but as a PoC, it's great!
Looking at those posts in your "UA Trending List" and the order in which they're placed, I think it has potential to be implemented Steem-wide / Condenser-Native. Of course, it only (now) contains recent posts published by the @steem-ua delegators (which could be solved if all accounts delegate to @steem-ua :P )
Yet more realistically speaking (hey, one can dream, right!) a "UA Trending Feed" should include all accounts and all their posts. Every account does have a UA score, and so does every post, regardless whether those accounts are delegating to @steem-ua, or not.
I agree the current UA-API doesn't fit those requirements. Implementation-wise, I wouldn't recommend an infrastructure to deploy a UA Trending Feed being dependent on an external node and the UA-API. Instead, how about locally running the UA-Python Lib (sourced / linked-to in this post), circumventing Hivemind, and doing a UA Trending PoC based on all Live UA Data?
(PS: as you might know, I got tired of the "personal bashing" and "social / political quarrels" associated to UA / @steem-ua. Personally, I don't feel too comfortable going that route again by self-developing the UA Trending PoC as explained -- this is an understatement even. Yet I've always had nice talks with you, so if you're up for the challenge, I'd be happy to guide you towards an implementation as mentioned in this comment.)
Here's another idea. Issue daily Steem-UA tokens based on the rank or whatever criteria. Maybe token issue would be based on rank alone, regardless of post frequency. Or maybe it's a combination of rank and post. Whatever, doesn't matter.
Then, anyone can look at the sum issued over time to the account to determine rank.
I do something similar here, in my STINGY token report:
https://steemit.com/steem-engine/@inertia/stingy-news-the-stingy-oracle-is-still-stingy
That report doesn't simply look at the rich list. This is the simple rich list, see the difference?
https://bloks.xyz/token/STINGY
My report shows how many people earned STINGY. The rich list shows how many people have earned + bought (market trades), so the rich list might be less interesting.
I could see a Steem-UA implementation leverage this same dynamic.
Maybe you always issue 1000 tokens every day, but it's divided by the top accounts according to the current Steem-UA rank.