That’s putting it mildly.
You probably saved yourself some potential frustration.
I think it’s mostly with the stats and damage output, especially from the bosses. Considering stage mechanic, the mobs lawnmowers you down for their boss overlords, who was all too glad to show up for the kill.
Athos is a very big problem, and I actually didn’t bother reading his card until much later, green sniper charges on very fast and bypasses defensive buffs (including ripostes), and because the modified shields/diamonds are only removing their Riposte and damage reduction buff, but not their actual damage output and not affecting their mana or attack speed, any popping of the now modified dragon shields / diamonds (they go horizontal and vertical), it often times will trigger other potential un-favorable colored tiles to charge up the bosses.
Athos with a special, was doing some overkilling 1200 - 1500 per damage shot (again, bypasses defensive buffs) per shot, easily can pick off a single (even somewhat overhealed) 3*, and D’Artagnan and Aramis aren’t exactly pushovers either. So most of the time, even if I was able to save my specials up in time to fire against them on the boss wave, a few moves later I am dead, there is nothing I could do to stop Athos if he is doing that much damage on a single shot.
So, after the adjustment, mobs were noticeably less strong, I was able to apply a few layers of Overheal coating with Grevle, and heading into the boss wave, I am obviously now doing more damage on the tiles, and Athos, even on a slight attack debuff from Treevil, did about 400 - 500 damage on my 3*, which survived because of the overheal, but you can see that was at least still manageable.
I finished Rare-10 in one try after the “adjustment” gate.