Level design is pretty garbage and constantly uses big setpieces to herd you through it.
The first part is mostly linear disguised by sheer drops and level design during Dregs never goes beyond Farron Keep levels of good.
The game briefly opens up in the ringed city but fundamentally it's a small quantity of higher floors and bridges above a staircase.
Then it pretty much goes right back to a swamp leading into a linear path to the end of the DLC.
2Demons is modestly interesting with 2 bosses swapping between ranged and melee for a total of 3 configurations but them clipping into each other makes the double melee configuration just a time waster for anyone not wanting to waste Estus. Second phase 1Demon is just kind of tanky and mostly just about avoiding high damage attacks by recognizing tells and doing the right dodge.
Spear of the Church is a player boss. Not very well thought through and entirely unoriginal but fun enough I guess.
Gael is an Artorias ripoff in a wide open arena. Decent enough but lacking in payoff.
Midir is a tanky enemy that is large. You see and fight him earlier in the DLC in a manner that rips off most of the dragons in the souls games and then truly finish him off in a mediocre fight with kind of lame attack patterns. Can't even cut off his tail.
Enemies vary at least even if many of them are straight up reskins but the placement tends to be bad and several are scripted to only walk out their patrols or rise up out of the ground when you get near so that tends to be annoying.
Game kind of cheaps out by having several potential enemies just be NPC invaders.
New weapons are alright though mostly I've just been using the Halberd and the Doors.