Please Help Me Tune My Man

[Teleolurian]

Charm seems like it would be most effective versus the quality-troop nations, i.e. Abysia, Jotunheim, and maybe Ulm. Well, maybe I'm just thinking Ulm because of their low MR. After having read this thread, I can certainly see adjusting my on-the-fly strategy to take advantage of this spell if I find myself neighboring one of these nations.

Hellbind Heart also sounds great, but for Man would require branching into blood. Is it more effective than Charm, or is it just the lower research cost and the fact that it requires easy-to-harvest slaves?