I prefer not to turn this into a numbers and stats game by thinking about it too hard. It should probably just be determined on a case-by-case basis as makes sense.

Being so literal with Might would also mean that the elementals would be disproportionately powerful by this standard (I think 1 Might, some of Astarte's magic-in-a-jar, and then his domain powers over Change were used in their making), though maybe that's fair since Zeph did break the rules and subsequently got punished.