Has anyone mentioned bad loading times yet? Because that is the worst. It sends a clear signal to me that I'm going to be constantly jerked around between fun and tedium. Who wants that? Then I stop being immersed in the game world and instead think about tricks to avoid the loading screens, like "let me avoid that area for now and grind or collect in this area so I don't have to wait for the game to render a new environment". You realize how terrible this is when you play other games after Mario 3D World, a game that consistently stays above 60 fps with extremely short loading screens.
Number two is drip feeding game mechanics. Not just "hand holding", but drip feeding Hand holding is annoying, especially in long running series. But I can tolerate it if it doesn't go on too long and it's woven into the atmosphere or story. For example, if the game makes you learn combat mechanics by having you train with a great master, or something like that. Think Wind Waker. Drip feeding mechanics, especially in a checklist-style manner, is the absolute worst. Developers, you don't have to throw 15 possible button combinations at me in the first area of the game and superimpose a check list on the HUD. It just makes the game seem like a chore instead of getting lost in an immersive quest or adventure. In general, don't break the fourth wall by superimposing button controls on the screen in the middle of the action and don't combine that with endless checklists at the beginning of the game.