I think the damage level done by Great Trolls is probably correct - remember most Heortling warriors will know Strength rituals that will knock their damage up to around 7 dice.
My proposed solution is not to reintroduce the INT stat back into PDP, but simply create a new arbitrary training limit for Great Trolls - say 10 instead of 15. Additionally a pitifully low maximum memorize (or starting the skill at 0) will keep them from having much magic.
Jeff
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