Thanks for the suggestion, I completely agree that keyboard controls for plugging stuff in could have made it much more streamlined. However I could not settle on an intuitive way to pick which socket to plug/unplug from, so I never prioritised it on the todo list.
I like the idea of using a button to toggle through all the options, but that would require a second button (one for toggle, and one for apply selected), and it was really important to me for it to be as simple as possible, and mouse was the most intuitive way to do that. That's the reason behind the decision for mouse over keyboard!