I made some comments in other threads but I think this might deserve it's own for visibility. I really love the look of the new Fenris armor and the speed bonus instead of penalty is awesome. And I like making fists a viable skill, especially since it reminds me of unarmed in Asheron's Call (all of Valheim reminds me of it but I digress).
That being said I have some issues with the implementation of Fenris armor. It seems too difficult to obtain and doesn't seem to fit in the pattern of the other 'light armor' options in a tier-based progression system.
Note I'm using the fully upgraded stats here, so that will differ since workbench levels are also gated but it should play out the same even when you take that into consideration.
All of the light armors so far (seem to) exist as an alternative to the previous biome/tier's top armor, and have a useful mechanic for the biome you get them in.
Troll (40, Black Forest) is slightly better than leather (28, Meadows). It buffs your sneak skill, which helps you stay undetected by things like trolls and brutes and can provide a damage buff to take them down. Note: Meadows has no metal armor option for a 'top tier', I'd like to see maybe a bone armor with ~32-36 armor here or some other sort of 'heavy set' for the meadows. Maybe a small (+5-10) base health bonus?
Root (46, Swamp) and bronze (46, Black Forest) are similar levels of protection. Root has poison and pierce resist which helps you survive swamp mobs like blobs and draugr archers.
Fenris (52, Mountain) should therefore be similar to iron (64, Swamp) and less than silver/wolf (82, Mountain). It has fire and frost protection to keep you from freezing, and protect you from cultists and drakes. Plus a run bonus to make it easier to get up and down mountains.
Based on this, each piece of fenris armor should probably have an additional 2-3 armor for a total of 58-61 armor, at least.
The benefit of the light armors is that they require little to no metal, which means you can collect materials and still travel through a portal. This is incredibly useful for someone who is just starting a biome and has not established a base or outpost in the new biome. The materials come from mobs, which means they are plentiful because mobs respawn vs a limited reagent for metals.
Troll armor takes 64 troll hide to completely upgrade (not including cape for 3-piece comparisons). Each troll drops 5 troll hide (for zero stars).
Root armor takes 66 roots to completely upgrade. Each abomination drops 5 roots (no starred aboms AFAIK)
Fenris armor takes 150 fenris hair to fully upgrade. Each cave gives you about 10-20 hair. And once you finish a cave, it never respawns, unlike the trolls and aboms. So you likely have to visit multiple (2-3) large mountain ranges to finish this armor.
It seems ridiculous to require 10+ caves in order to complete the armor. I think a lot of people are overlooking this because they've progressed beyond mountains and find it easy to return to them. But for a new player just finishing swamp, traveling to multiple mountain ranges to find caves is a fairly daunting and dangerous undertaking, especially if they have to traverse the sea in a longboat/karve to do it.
It's actually easier to find multiple silver veins to get enough silver to craft Wolf armor vs finding enough caves to craft the Fenris armor, which provides less protection.
Therefore, Fenris armor should have it's material cost reduced by about one third or one half, and caves should increase the amount of hair you get per cave by about 50%.
In it's current state, Fenris armor is a niche novelty item that looks cool and serves little purpose in the game's progression system. I think some balancing could definitely be done in order to make it a little more useful and provide players with more options during their progression (for instance, a lot of players skip bronze and go from Troll to Root, or Troll to Iron). By increasing the protection and decreasing the material costs, it would put Fenris more in line with the other armors.
TL;DR Fenris armor should give you slightly more armor, and cost slightly less to make in order to be balanced properly with the other 'light' armors.