I hope this thread isn't too offtopic, if it is and it violates a rule please delete it and let me know.
I wanted to ask you guys what your opinion is for using a real language in a story i am planning to write, based in a world im trying to create. I have no problem inventing words and place names, but my native language (Romanian) is pretty unique, in that its the only romance language to have a slavic stratum to it (about 30% of words are slavic). It can be understood only by Romanians, so for the average non-romanian reader it would seem curious and strange, perfect for one of the "cultures" i have in mind.
Would it be a bad idea to write the bits of language in romanian and those local place-names also, or should i invent everything on the way?
So you guys get a picture of how this language is, its ~ 50% mutually intelligible with Italian, but the similarities end at the words themselves, the grammar and synthax is very diffrent.

Waiting for your impressions, critique is welcome!
A good day to you,