In my opinion this DLC is very unfairly judged. I read the comments and was turned off from it, since people said it was unbalanced and boring and nothing like the base game.
I LOVE wartales and wanted more of it, so I got the DLC anyway and I was very positively supriced by it! I don't think its very unfair at all and after having played it I am confused people claimed that! Sure its hard, way harder then the base game. But then again it is a tournament and not just regular combat scenario! You have to play it a bit like a puzzle game and read all the different modifiers properly and plan for them, I think it changes the combat quite a lot in a positive way. The base game has so many oils, belts, gear, skills, etc, that alter debuff effects, but in the actual game these belts aren't usually as valuable as items that modify critical chance. This DLC changes that!
All the arenas are interesting and focuses on different debuffs and modifiers, the way to win is usually not by just engaging in combat, rather you have to use equipment that is suited to the arena and use your environment to deal debuffs to the enemy. I really like this arena setup since it forces the player to actually use the environment and think about debuffs, you cant just run through fire and potion like in the base game without a care in the world. For instance when you fight plague victims they heal by potion and there is a lot of potion plates, but if you are smart you can potion them anyway and use gear that deals more damaged to potion enemies and pretty much one shot them and there are belt accessories that make you imune to potioning, flames, etc. So I don't see why people complain about debuffs.
I would say if you like the regural arenas in the game this is a big improvement on those! The gear you get as rewards are really fun as well! They lean in too using modifiers and if you build your character around that you can get some really interesting results!! The only small thing I "dislike" is that I wish the gear that was rewarded was a tiny bit stronger, I feel like the level and gear you have to have to enter the arena is pretty mid game (around level 8) and the rewards damage output is a few level bellow that. So I still feel like the tomes offer better rewards.
But you will also unluck new outfits, potions, belts, etc that are really useful!
All together I really enjoyed this DLC and think it offers a fresh change from the base game so if you like turn based puzzle games and the debuffs and modifiers in the base game, I would recommend you to give this dlc a chance regardless of the negative reviews. I had a blast with it!