Which plaintext languages to try?

[Addsamuels]

Thank you, Marco and Rene, for the feedback. I still feel it's about time I started thinking about plaintext languages.
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Just to make it clear, I'm still not sure whether I'm on the right path, it all looks very plausible, but I have no definite answer to any questions yet, including any specific words, images or marginalia of the manuscript.

It is also certain that if the language was a plaintext language, then it would be an archaic or obsolete form of this language or potentially a dialect. The languages I chose, was based on a chart from Dr L F Davis and the provenance of a likely European language. They also form multiple language families too (although they are all indo-European, and the manuscript like is too, if and only if it has a plain text solution