[Plane]

technical grappling 28 has "(Limb) Grip ST" limitation for Lifting ST for "applying to only one set or type of limbs"

which I figure benefits not just hand stuff but also other no-hands stuff you do with arms

to narrow it further to JUST one arm, I'd speculate doubling the limitation value like Damage Resistance does, from -70% to -140% although I don't know what sort of enhancements you'd add to benefit from more than the extra -10% reaching the -80% cap

DR treats "hands only" as twice the value of "arms only" (not sure if arms only protects hands too) so should that double it further to -280% ?

at that point I'm wondering if we should have something like this custom house-rule enhancement:

"Extra Level +100%"

I've thought that would be cool to have for DR too, to explain why you'd bother taking more than -80% in limitations for DR that you didn't want to take some of the four standard enhancements (force field, hardend, refleciton, absorption)

this could be part of a broader "Improved Levels" spectrum of multipliers, where you just increase the level of your advantage by a % equal to the value of the enhancement, so +100% levels (double) for +100% enhancement, +200% levels (triple) for +200% enhancement, and so on