Probably the %meter gain, %atk, %def. I suppose it matters a little if you already have defense maxed out, but in most cases %crit dmg is worse than %atk because you don't crit 100% of the time, and even more so because as I understand it %crit dmg can max out, which you'll likely encounter with Primed, while %atk can go as high as it wants.
%Crit rate would be a different matter. You probably want as much of that as you can get on a Primed.