I think an easy change might be that instead of eternal rage, just put rage on shred, and use feral invocation with furious slam + aftershocks. Freeze, break armour, then invocate a bunch of bear slams for the coup-de-grâce, or repeat as necessary.
Lunar blessing and wolfpack works too and all the nodes that gives you dmg per companion surrounding you. The main predator mark that comes with pounce is good when you get a big wolfpack going on. I find that freeze buildup is already good especially with the howl - you get more freeze buildup from the "freeze" support gem on lunar assault than you do the mark. Maybe preference here.
Also I think uruks smelting on ice bite is kinda waste - I guess your "brittle armour" support in the howl is supposed to make it so that when a monster is frozen specifically by the howl, the 2nd monster (which is also frozen) next to it gets armour broken from the explosion of the first monster..? Feels kinda jank lol. I've never used that interaction before though maybe it is smoother than I am imagining.
I think people benefit most from this when there is also the perfect essence prefix on the talisman for "gain 20% of damage as extra physical damage" that way the herald of ice explosion does phys dmg also and then you can just make that phys dmg break armour. I don't think herald of ice has any inherent armour breaking capabilities.
That's probably related to why your damage feels bad for boss fights. They have tons of armour that you're not breaking until you freeze them specifically with the howl and then when their armour is broken and they're frozen you're only seeing a 20% more bonus to your existing sustained attacks.