For me shadowbringers has been the worst expansion so far, the story and the ascians part was really great but the whole warrior of darkness thing end being just a question of semantics to make silly jokes like "we are the bad guys now right?" Was really poor for me, would have been a lot better if they call us the shadowbringers instead of the choosen ones to wield the power of darkness to fight the light, zenos still being around don't help either but that's just me.

The other thing I don't like about the expansion is combat content and how badly they did with tanks and healers with all the simplification and reduction of the roles and jobs identities to the minimum expression like DRK, AST and SCH, the reduction of combat content in terms of quantity, durability and difficulty has been a total step back and being forced to play DPS to have a minimum of fun outside of my savage progression it's not fun at all.

Other questions like how bad the development of viera and rofhtgar has been are in my mind too, so idk if the combat changes are just a step for a transition to big changes but I consider they did really poorly for tanks and healers, so I hope they do a lot better for 6.0, SHB have some nice stuff but have the most amount of flaws for me.