Awesome ! Is there any posts that you feel are out of place ?

Quick question on the timeframe: was it intentional to include posts older than 7 days?

Yes, I've decided to include them so that people don't miss out on them, but you raise a valid point, curation-wise it's a bit useless because they are past their payout window.

Also, not sure how feasible this is, but it would be awesome to occasionally surface some undiscovered or under-rewarded hidden gems,

This is kind of the goal of the algorithm. But underdiscovered gems are, well, by definition underdiscovered so it's hard to find signal for them. That being said I could see a future where you can specify a list of accounts you really like (eg: curation guilds) and whatever they comment/vote on has a strong score for the algorithm.