I've played For Honor since release and I've had disappointment after disappointment as time has gone on. List below...
-unbalanced heroes (primarily new heroes since marching fire).

-barely making any steel therefore forcing players to buy the year passes to try new heroes as well as upgrade gear. Also forcing them to buy steel or play for a month straight just to earn that 15000.

-due to the unbalanced heroes, the perk system is broken. The old system was better, upgrading gear meant something. Better attack, defence or revenge gain. Even better combine the two.
-in ability to sell gear for steel. This should have been a thing on release. Salvage is useless if you can't use it.

-the warden needs new moves. Other heroes have had improvements whilst the warden is left and forgotten.

-guard break needs a slightly wider counter. Too many times I've pressed square to defend against it and nothing happens, sometimes I've pressed it first and I'm the one who's guard is broken.

I'm hoping that others out there also feel these changes need to be done to give us all a better gameplay experience as well as forwarding things they feel need to be addressed.