The 'magus' idea you mentioned gave me the idea of a series...
magus that perhaps heals you for every creature played.
magus that buffs the attack power of any friendly creature summoned.
magus that affects the opponent, delaying their creatures.
magus that weakens the attack power of any enemy creatures played.
magus that boosts the HP of any friendly creature played.
magus that reduces the Max HP of any enemy creature played.
magus might require a quanta upkeep due to the first power that comes to mind, granting immortality to any creature played.
magus could grant the passive 'airborne' to friendly creature played.
magus might scramble a creature's skill cost, making it cost a random elemental quanta, including rainbow.
magus could grant momentum to friendly creatures, at a quanta upkeep price.
magus either grants biolumence, or perhaps heals all creatures when a creature is played.
magus could 'refund' you 1 quanta of that creature's element when played, essentially cutting down on the cost of summoning creatures, in a sense.
quanta upkeep seems to also be a potential balancing factor, and this list probably could more or less be straight converted into permanent auras.
Yet another idea, one I kinda like, is this effect as a spell, that provides this buff to the next creature summoned. I propose that the permanent, creature, and spell buff ideas be appropriately scattered throughout the elements, so for example,
's effect becomes a spell, alongside quintessance, but working instantly, while
's effect, due to it's situational nature, be a permanent.
Any ideas you'd like to add to this list OldTrees?