Odds are you'll start accumulating the assorted corruption-related flaws pretty soon, but then again with that kind of income at least the financial penalties are irrelevant. When the Civil War started (and caught me a little pants down) I had over 100,000 denarii in the bank, and after twenty years of two-front war with Egypt and all the other Romans at once I still had about 20,000 left when I captured the last of the fifty provinces.

If you're not the Brutii and they own Greece, it's well worth trying to kick them out of there. Actually, scratch that - whoever owns Greece, kick him out ASAP so the money gets decent use.