I thought about this a lot when making my Mando'a translator, and noticing the relatively small lexicon. Most words are made simply by joining two words together, which is fantastic, but sometimes you really really have to stretch to figure out how to make a new word, often requiring use of a thesaurus to help find a barely-related stem word to use as the root.
As one also deeply interested in linguistics, I love the idea of creating entirely new word roots, but I would recommend doing it very sparingly, and only in the case of dire necessities. There would, indeed, need to be much discussion and agreement upon these new word roots, which would be time-consuming, but possibly worthwhile in the end.
And when it comes down to mutual intelligibility, we can just chalk it up to us having our own isolated regional dialect. Sort of like how Chinese shares almost nothing in common with languages like French.
So to sum up my feelings on the topic: brand new root words...eh, maybe, just be careful and use that power *very* sparingly. Use a thesaurus whenever possible, and possibly, instead of adding new word roots, consider expanding the definition of an existing word to explicitly include the word you thesaurus-ized.
Am I making sense?
Oh, and as for keeping track of them, I would be glad to add an alternate dictionary database to my translator to keep track of these changes. That way, people can look up "Core Mando'a" in a separate dictionary from "Our Mando'a."
And to answer the question about legality of my translator: yes, I have permission to use it. LFL responded to my request last night and said they're cool with it, but I am to remain non-profit and unaffiliated with Lucasfilm.
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