I use The Core hotkeys, and I’ve had “I” mapped to Return Cargo for years, so it’s built into my muscle memory. My hotkey for unburrow also happens to be “I”, and for years that caused 0 conflicts because burrowed drones cannot return cargo; they do not have that command.
With the Arcturus Mengsk patch, the unburrow for Stetmann’s Mecha Drone somehow made its way to the unburrowed drone’s command card, and this caused my Return Cargo key to be unmapped. Now I’m having to re-learn muscle memory, and it very much affects the quality of my play.
A simple fix would be to once again have the “Burrowed” command card for the Drone separate from its “General” command card, and remove the “unburrow” command from General, to be replaced with “burrow”, which I have on the “K” key.