Don't forget that each culture comes with 3 main gods (that will play differently one from the other) and with 24 possible pantheons (3*2*2*2) that will all have their own gameplay, some more ofensive (military bonuses, improvments of Mus, ...), some more economic (economic techs and GPs, ...) some more defensive (bonus to buildings, walls, towers, ...).
Playing two greek players (for example) with pantheons that do not intersect ( 4 gods each, all distinct), they each have 4 GPs, at least 4 MUs, at least 4 heroes, sometimes some unique regular unit (myrmidons for Zeus as an example) and somewhere around 12 techs and bonuses and none of those are common to the 2 players. Those two greeks will be much much much more different one from the other than any two given civs from AoKTC are.
My guess is that any two greeks (or norses or egyptians) with different major gods will be more distinct than any given two civs from AoKTC are, even with the same choice of minor gods. And that the distinction will increase with the choice of different minor gods.
One will say : "I master the pantheon Zeus-Athena-Dyonisos-Hera" well before he can say "I master Zeus" and even longer before he can say : "I master the greeks".
We'll play this game for more than a few weeks...
************
À la guerre comme à la guerre