Last question (I hope) on magic learning strategies (Machaka or similar multi-path)?

If you're pretender is built for bless effects, go ahead and build some black hunters, if he is not built for bless effects, stay with hoplites (Machaka has the best hoplites in the game) and archers. You are forced, because you have no access to communion to rely on forged items to increase your magic on your mages.

Spells that work well with Machaka:
Magma Eruption (Put Earth Boots on a Black Sorcerer)
Blight
Relief (Sorcerer with Nature Stick)
Summon Earthpower
Reanimate Archers (Black Sorcerers random is in death)

Eagle Eyes/ Combat spell (For Sorcerers)

There are more ideas in Alex's Tome of Knowledge as well.