All of the controllers I come across lack a undo button, which to me is vital when laying down recordings. Am I overseeing a controller? I asked M-audio if any of the extra buttons (like the arrow keys) on my keystation 88es would be mappable and this was their answer:
The possibility to map the controls on the Keystation 88 MK3 to an 'Undo' function will depend on if this is a mappable function in the DAW you are using.
From the information provided, you are using FL Studio.
Please contact Image-Line/FL Studio support for further information on if this is possible as this is a 3rd party DAW in which our support is very limited.
It doesn't have to be a keyboard controller but just a transport controller would be sufficient.