Configurable double-tap and hold
Offer a less motor-demanding alternative wherever these actions are required, in the same way as being able to configure double-click speed in Windows.
No matter what amount of time you choose, it will always be too difficult for some and too frustrating for others, so being able to configure it allows everyone to operate those core commands in a way that suits their own abilities and preferences. Being able to set up an alternative to having to double tap or hold would also be helpful.
Configurable double-click speed in Windows