I still think you're going to struggle with the ROI issue, if delegators need to share with authors of old posts then they're likely going to be getting lower returns than the de facto 100% self-voting of the currently-established bots.

Maybe. That's why I hedged my one statement about ROI with "conceivably". I guess there's no way to know without running the experiment. I like this idea:

Maybe have the selection criterion focus on old posts from currently-active creators, so there's a clearer link for how the incentives could work?

I'll probably add that to my list of screening parameters. I was thinking about adding a check for number of active followers, too. Also, once the whitelist feature is added, a Thoth operator could limit it to just a specific set of trusted creators - which offers a more direct patronage style of relationship.

Maybe tracking follower growth for Thoth-featured creators would be a useful metric for you to track to judge how well its working.

You're way ahead of me here. This is definitely a good idea. I hadn't even started thinking about measuring success.

I'm not sure there's enough organically-voted SP for that to work out.

Probably true, but hopefully not forever.