I think it's a good idea to pit chariot armies against the young upstart Greeks!
It will be interesting to see how Egyptians (for example) deal with a wall of Phalanx.
Almost enough to get me out of retirement
Of course Sumerians against Burgundians would NOT work!
But on the whole I'm comfortable with Biblical/Classical mix.
At the last 'Biblical' GT I ran, we got 30 players, which was down on the previous years 50, so it is a rather obscure area of ancient gaming.
It's the route I would take if I was organising a CoE event.