1. nostr is already integrated and automated so ~nostr should grow organically. if they don't come then the solution is probably to be found in tuning the SN nostr automation more than manual action.
2. ~lightning / ~bitcoin / ~bitcoin_mining doesn't align with the targets you went to - you seem to have been wading into generic normie(-tech) space. however: ~bitcoin_beginners may be a good target
3. ~econ is interesting, but I think it is a hard target to start with.
4. ~tech is dominated by hn reposts, no one will come here for a bot.
5. ~AskSN and ~AMA are VERY interesting as drivers because these host unique events. But that should imho be done with a bespoke marketing process for each, and they're event-driven, so it makes sense for marketing to be event-driven too.
6. ~AGORA - i think that one is being taken care of well!
7. ~Stacker_Sports is the closest to a true sub-community (of y'all degens, lol) and should probably have a bespoke growth solution.
8. ~Politics_And_Law, ~Stacker_Stocks and ~news are hard, I think those are serving the "internal SN audience" more than the outside (~AI too, but I can influence that a little)

~DIY and ~security, with a 2-3x increase in content, can be good ones to start with I think, due to the techy nature. ~privacy could be awesome too (but expensive.) ~the_stacker_muse would be EPIC, I think, but I would have no clue how to approach that.