Besides Romanians, there are several more eastern european romance-language-speaking peoples ("Vlachs") like Aromanians, Megleno-Romanians and Istro-Romanians. I think they might also deserve a mention.
Romanian is isolated now, but even quite recently there where languages forming a bridge between Romanian and the rest of Romance languages. For example Dalmatian, whose last speaker died in 1898. Now, most people think of Dalmatians as the dogs.