The current way to access the energy menu (E key + move mouse) and activate your shield, for example, can be hard to use in the heat of battle. Often times I will try to quickly switch to the shield but moving the mouse to the side to do that is too innacurate and often times I have to try a couple times or more before it finally deploys. I instead propose that this menu is changed to keys such as 'E', 'R'. and 'T' which could be used to activate increased speed, shield, and damage boost respectively.
I have heard many other players voice the same complaint since early beta but nothing has been done yet. I hope the developers will finally listen and change this.
EDIT:I never knew that you could use F1 - F3 to do all this. Thanks for pointing this out. They should just tell players this in the tutorial.