Some greek names are wrong ( I think)

[Tiberius Nero]

By the way, would I be correct in assuming some snobbery leading to conventional Attic being the dominant dialect among elites during the time in which Koine was developing, and thus much of EBs period?

Just wondering - could be an interesting (language) trait if so...

You would be correct to assume something similar for the next 2000 years or so after EB's timeframe actually; up until less than 40 years ago the official Greek language of the modern Greek state was a simplified form of Attic/Koine, called "katharevusa" ("pure language"), used by scholars, state officials and the Church (the Church still uses it for its official documents). Modern Greek is a mixture of the katharevusa (much vocabulary derives from it) and demotic Greek.