I opened a thread on this topic:
http://elementscommunity.org/forum/index.php/topic,21847.0.htmland came to the following conclusion:
for eternal crusader: standard mono aether (with 6 dragons and 6 dim shields)
for serket: modified mono aether with mark of water and 3~4 purifies
for jezebel: modified mono aether with mark of earth and 6 enchant artifacts and a couple of lightnings to deal with air nymph (hope jezebel doesn't get an air nymph, if she does, hope she doesn't chain too many cloaks)
for akebono: liquid antimatter
no one has any idea on hecate yet... (tho I think an earth/gravity duo with gravity shield and enchant artifacts, along with earth's SS for healing to survive the voodoo damage, and momentumed colossal dragons for damage, I dare you, hecate to use rage elixirs on my dragons)