There are stuff in deference in heroes in each Civ as for example in Ptolemies we can have a variety of uses in all three heroes for example Ptolemy IV is good for defense as triangle 20 pikemen with him and hold a ground and something and if celophatra VII for attack and Ptolemy I Sorter for using in home defense as after attack easy to rebuild and form a new army to attack and he is a good seige. But in some Civ like Britons we mostly take Boudicca as its the only one with decent attacks and speed as if we send 5-10 more carrtios it would make a decent army but the second and third are useless as for seige in Britons no one needs it garrisoned as we use Britons only for rush and most games never train an hero waste of time and in Athenian we never mostly pick ( expect naval battles) and only pick any one for the three as mostly the three of them as useless in land. So, it would be better to give all heroes decent boosts or attack to make it balanced.