God of War (2018) - XP system.
The game just isn't that fun until you have those weapons highly leveled up. Wasn't a problem in any other game in the series, but the combat was kinda boring until Kratos got powerful (imo).
Halo Reach - Loadouts/Armor Ability
I'd change a lot in Reach but an arena shooter with loadouts kinda defeats the purpose. Let me pick up all of those sweet weapons and lose the special armor skills attributed to each one.
Yakuza 6: The Song of Life - Phone crimes
These phone calls drive me nuts. I don't know why they thought it would be a good idea to phone me every minute to fight a criminal as a vigilante when the crux of the game is fighting criminals every two seconds. Why add the middle man with an annoying ring?
Probably A LOT more I can think of. Most of my MAJOR issue with games are nitpicks to most people so idk why I'm drawing a blank now but I'll report back.