I'm gonna bump this, since I just found out about it, and I've been "working" on the same thing, though I haven't done anything in a couple months, since I haven't been that interested in DF at all for awhile. Probably because of anticipation for interactions wearing out my patience for the current version and ideas filling my head about curses and mother grubs. I'm definitely gonna use a lot of what you have, though it means I'll probably never publish a full MSPA mod myself.
The files I have are modded from Aqizzar's(who is the creator of the version you were probably referencing in your first post). And I wanted to discuss some concepts you have, from looking at your raws. First, I really like how you did your caste differences. I don't think mine is quite as well thought out. I do think that you should have jade a bit more common(though rare, I'm sure there have been more than twice as many jade bloods as red bloods, since troll society actually knows where they belong). I have them set to be as common as the highest purple, though they're both too common in mine right now. Also, I set up kind of a weird age ratio thing, that has lowbloods living significantly shorter lives than their highblood breathren, to counteract the increased numbers, and because it's pretty canonical. Maroons live to at most 60, while Fuchsia can live as long as 500 years.
Oh, one thing I really wanted to ask was why you don't want them mining, when they're supposed to spawn underground?
On royalty, yeah, you did a lot better than me here too, though I think you should have included Slam Poets as a sort of broker/diplomat hybrid. And I still think that subbjugglator should be a rank, since I don't know if it was ever said that it has to be a specific blood color, even if most people view it as such. But that's a matter of opinion.
I think that's all I've got for now. Gonna go contemplate how to add Dragonyyds or something. Once I actually play it, I might have more opinion.