I don't write in my main langage so please excuse me.
I will point out the main things that ticks me good or bad:
First : the story.
Appart for the main caracter, which is the last boss, the mongrel, the queen, the succubus, the assassin and the only demon lord we can work with, all others are pretty bland characters.
Second: narration text and overs
They are bland too. Take a monocord voice and read your favorite book with it : you''l understand what I mean.
Third: Graphism
They are gorgeous, way better than the previous opus.
Fourht: combat system
Well, I can't blame the devs for using D&D5, but it's really not my cup of tea. It feels boring and you don't sense the power gained, even with the mythic system. Sometimes you get whiped out for nothing.
Spells are useless mostly since resistance against them is superior than your ability in most cases, rendering spells like laughing and imaginery assassin pretty much useless.
Also, why stop the growth of characters at 20? It's rendering the unfinished quest and comabt greatly inappiling.
Finally fith: mythic system
Without that, the game would be plenty boring. It let you incarnate the parangon of one out of ten archetypes (based mostly on the moral system).
It increases replayablity a bit, bu since a game is a 50-100h, you must have quite the patience to play ONLY for that...
Conclusion
All in all, the game is pretty average, with some unreasonable choices, particularly on stories.