I think you probably want to have snowrolling maxed for the AoE Ratio… It’s the number of monsters it can affect. Right now the end game has been all about waves of 20 mobs, large mobs, and large mobs have 3 AoE Ratio Def each.
So if you have snowrolling Lv1…
Base AoE 3, +6 from snowrolling = pickup 3 large mobs.
Capped Snowrolling you get total AoE ratio of 3+10 which means you could pickup 5 large mobs.
Or 13 small mobs max vers 7 small mobs with only 1 point in the skill.
That’s all before you consider head gear which you will want to have AoE ratio rolled on and any other equipment you maybe using. But you get the idea of how important AoE Ratio is for doing your job of controlling as many mobs as you can.
This can be modified if you snowroll at almost the exact moment of a linker’s hangman’s knot because of it’s attribute to remove AoE Ratio defense. Or if you’re lucky enough a Falchoner’s Circling ability would let you roll on infinite mobs assuming they were all hit by it and didn’t resist.
I would consider removing points from Ice Spike since the damage is a flat value. I wouldn’t take it out of Icewall since it determines how many times you can shatter each tile. So it’s a lot of potential damage to give up if you’re using Ice Rune + Ice Wall shatter combos.
Edit: clean up, slightly with more explanation of ice wall