Here’s a recently completed Ph.D. Dissertation posted on Thought you might be interested:

The loss of the genitive in the diachrony of Greek

Ἐργάζομαι is a bit of a difficult verb to deal with in terms of voice. It’s perhaps the only verb that causes problems (at least at face value) after the rejection of deponency as a valid category for the Greek Voice System. Rutgar Allan categorizes it as an indirect middle (Allan 200, 54). That has always seemed a bit forced. But perhaps there’s some credence to it.