atm i take hercules, oddyseus and athene to war.
before (but not the direct war. i mean when i changed war heroes) it was [edit: i forgot the combo hercules,achilles,odysseus ] hercules, perseus and achilles.
before it was perseus, achilles, kadmus.
before it was perseus, achilles, jason.
ajax had its time quite a while ago. helen could be (but i still dont like her against hard GK).
for prom, ariadne i would need to forge more in particular
arthemis no way atm (but she definitely has potential)
as said before: every hero can be used if you have loot-luck or forge for them or you like the different play styles.
if find it important to have them all at lvl20, not so much bc of the strength but for the synchron and max fury cooldown.