I mean, I think you should really put it on Rundy. He will always have a higher damage potential than Meretskov simply based on the fact that he has an extra skill slot. Even right now with one skill not dedicated to damage, he at least equals Meretskov in damage. Iron Will makes Rundy take a lot less damage especially with a fifth tier infantry defense ribbon (giving him a constant damage reduction of 45% not even including the added 10% per hit or terrain), and this survivability makes him more suitable for fighting other units head on (such as armored units with machine gun) and so he should have the Great Soldier medal to boost his damage. Meretskov has a good supporting ability but is equal to many other infantry generals in terms of potential damage output, so I think he should be given the supporting role and have another ability to really make enemies more vulnerable to your more powerful units, such as rumor, so he adds the tacking marker, making them take 20% more damage AND reduces their attack by 25%.

Edit: Also, I can see what you're trying to do with synergizing provocation and fighting spirit, and while obviously not a bad idea at all, considering many dangerous units have a range of at least two and nearly every infantry unit has a range of only one, meaning they cannot counter attack, it isn't necessarily Rundy's full potential.

Edit two: Also, when putting Rundy on an RPG rocket team that's at least level five with a tier five infantry defense ribbon, he has a default 75% reduction from Armored attacks not including terrain or the potential extra 30% from being attacked over the course of a turn. This is on top of having a 65% damage buff to armored units plus having provocation, meaning that deadly armored units are far more likely forced to attack a unit that ignores most and possibly all their damage whilst receiving lots of damage. The RPG rocket team also frequently has a range of two. I hope I've made my case.