I think Haligtree suffers greatly from what plagues endgame in general, i.e. lack of new enemies. But I really liked the layout itself. The verticality of the end part of the city itself, the branches in the side part with a bunch of prawns and knights etc. Admittedly that verticality made me lose like a half a million runes (though by that point I wasn't really caring about them and so I was just going YOLO), but that's more because of enemies launching me over the wall or knocking me down (including the fucking revenants sometimes somehow aggroing from the bottom and teleporting on top of me while I was on a branch or a ledge).
By the time of the end game I switched almost exclusively to magic for bosses (I still kept my twinblades to smack random mobs) because I felt my 80 int was going to waste otherwise and Radagon was the apotheosis of all the little annoying things From Soft does to artificially increase the difficulty of a boss beyond what their actual move set would justify). Things like delays on top of delays, some unavoidable damage etc. And the thing is, even if you haven't played any other From Soft games (which I had), even be the end of Elden Ring alone none of that is new and as such fails to even achieve the purpose of boosting the difficulty, leaving only the annoyance.
I killed Morgott before he even reached me, so I can't comment.
I can understand how that may be hard to deal with for some, but personally I got the hang of it quickly. As in on 2nd or 3rd try, which was way too quickly. Which contributed to the diminished experience for me. Also, like I said, by that point I was exclusively going magic. With Malenia herself being the second reason I made the switch, because her hyper-aggressiveness when you fight her in melee makes for a boring fight.
And here's a thing about Malenia and casting: it completely screws with her AI. The moment you start running around and spamming spells she will just slowly go after you half of the time and most of the attacks she uses as gap closers are either easy to avoid delayed stabs or the Waterfowl Dance (which, like I said, I didn't struggle with much). Which still didn't make up for a thrilling fight, but between having to wait a week for an opening and actually fighting the boss the latter was somewhat more engaging.
Gael actually ended up sort of disappointing me too, though for kinda the opposite reason than Malenia. Which is that P1 is the kind of a fight that's my Achilles heel as far as From Software games go. I struggle more than I should on hyper-aggressive bosses that also flail all over the place like a meth addict having a stroke. And because of that, P1 put me on such high alert that the very first time I beat P1 I burned through the other two phases and killed the boss, experiencing no "climb" for those phases. Still a great fight, even if I preferred Midir from that DLC (and Friede in the entirety of DS3). And yeah, Isshin is an awesome boss fight.
I wasn't talking about ER in general, I was quite clearly talking about Malenia specifically.
Yeah, no, this is an outdated dinosaur of game design. The point of having options is to provide different ways to play for different people and increase replayability, not to trick people into a wrong choice. Options are meaningful by themselves, whereas the only "meaning" of putting trick options into the game is to make the player feel like they wasted time pursuing the wrong build.