i hope quests are good. doesn't look like they expand the game mechanics at all, just offer a different approach to existing gameplay. its still the same stuff, kill the easy troll, kill the same boss reskins, its just now they put them into a quest.
"dungeon quests" - ok? its the same thing you already do. kill the boss at the end of the dungeon. now they just added a "quest" to it. doesn't add anything new at all.
"monster quests" - same as above. take existing game features and tack on "quest" at the end.
"mini quests" - these have potential to add something cool to the world. they should use these to expand upon lore and make things like skirmishes between towns, expedition parties, wandering bandit groups on a mission.
"main quests" - seems like the same thing as dungeon/monster quests, except now with the oh so awesome fetch quests added in. these would be nice if they added story to the game. the king needs you to go kill the dragon because it harasses the town. the church wants you to get back their gem that bandits stole. when you complete these, they have an affect on the game. kill the dragon and the villagers walk around the town more. recover the gem and it physically re-appear in the church, and the church offers to heal you for free or something.