I agree, they really don't care about Stonewall, like the slingers don't care about moving to get in range of a target (or just moving) after an Impale from Tryggvi.

Ekkill was a cool character and had a cool ability! I used him mostly for his high STR and, if maimed, for that push+damage ability. His high Break was also useful... Dunno, he seems like the jack-of-all trades, in the Raider class.

Egil was super-useful against enemy AI, since it ignored his stonewalling! I consider that more or less an exploit, so I only used him in Hard playthroughs...

Interesting bit about the Faction TSs, guess it is for balancing.
My favorite fighter other than the archer hybrid Rook would be Ekkil. Good stats and though hard to place, fun skill.
I barely used Egil as I wasn't that interested in a human pure tank. I also prefer the broken personality of Eirik to the young kid that is Egil.

Note that BF's last strike never misses in Saga, whereas in Factions it has 33% chance to miss. Despite that, I rarely used the H&M brothers in Saga, even though I fear Factions' Thrashers! The reason is that their ability doesn't scale so well in higher-ranks. On the contrary I found myself using Raidmaster's (Egil) higher-rank StoneWalling much more often than in Factions, where rank-1 was all I ever use. Another raider-class who's underpowered in the Saga is Backbiter (Onef): that max-STR limit at 10 is too little! In any case, there was often better units to go with so H&M were in last place in my bench, along with Eirik (Warden).

I had no problem using one or even two of the brothers during the easy Innocent run, but I sporadicaly used 1 of them durign the Hard no-loss run. I preferred a well placed Hakon to a possibly crippling Hogunn.

There is a reason to their randomness though. TS are OP in the sense that they can cripple anyone even when at 1 Strenght.

I don't really dislike the randomness in the Thrasher ability, but I'd rather have "deterministic" units both in my party and in my oppenent's... It makes the game much more predictable!

The worst part with Thrashers is that they are the only units in The Banner Saga which have "luck" based damages, making their use / counter hard to predict.

Aye, my feeling was that I had lost as well. Stats were approx equal, but the lower mobility of my SRM hardly compensated his passive's mitigation of BF, especially if he got a WP-loaded STR attack from the healthy Thrasher...

Hmh a hard one.
I'd say the TS team as they boost each other's armor, and can be a pain with Bloody flail.