Okay, I think I can safely say at this point that the material itself is working fairly decently (and I'm interested in this world, even), but... This isn't much fun in Play-By-Post?

It feels like work, since there's no banter over the choices being made, no tossing ideas around loosely; it's just a bit of a slog done this way.  It would need a different framing for "How to run the game in PbP".

Rather than asking everyone to slog through, I'm thinking I should get myself a live test of the current stuff, then write up a streamlined PbP procedure, and come back fresh.

Fair?

The banter is definitely missing. There's no... interplay.

That seems reasonable if it isn't producing like you expect.  Definitely agree that it isn't as collaborative worldbuilding as it could be the way we were engaging with it.  Still, I gotta say, that even running non-optimally it was producing stuff that I was interested in seeing where it went.

Feel free to hit me up if you need bodies for a live test though.  I'm interested in seeing how this works out when it is running properly.