Really I wanted to use Esperanto - that's one of the most Societist things from OTL - but that would obviously have been far too anachronistic to justify. Mindful of Bill Bryson's description of Esperanto as "looking vaguely like a cross between Spanish and Martian", that's kind of what I've tried to do with Novalatina - mostly a halfway house between Latin and Spanish, but when I have to make a decision whether to use a C or a G or whatever, go for whichever one looks strangest.
On reflection, I've just realised where I first got the idea - a science fiction novel I wrote in about 2002, where I wanted to nick the Spanish ranks from Brian Herbert and Kevin J. Anderson's "The Butlerian Jihad" but change them a bit, so rather than primero, segundo, tercero I used primerus, segundus, tercerus...which just looks weird. A combination of that with Star Trek authors who'd used Latin Primus etc for Romulan ranks (because they're Romans IN SPACE).