Expanding on these: 

-We've definitely got to let them have a little bit of their "honeymoon period" (if it's even called that yet since they're not actually getting married, I liked your synopsis of it though gave me a good chuckle XD) Up to you how you feel that should go, we could summarise it and then skip forward if you like or we could spend a couple posts on it and then do the skip forward? 

-I REALLY like the idea of combining both too, Renso finally realising he's going to croak and frantically reaching out to Ari and Bol as the only two people he can "trust" with the most advanced of his teachings. They could then like you say journey back to Zinuthra to meet up with everybody else (yay, reunions!) and fill them in on what they learned from Renso and set up the training etc. to make sure it keeps spreading to Force users in the galaxy.

-All the yes for creating this ancient species, I can't remember if we talked much about what they'd be like before but the Chiss might be a good place to start (though I'd have to read up on their lore again XD) Were they going to be more technologically advanced and a bit like the Rakata or were they something else entirely?