If you don’t want to lose out time on selecting towers and navigating around the map you should internalize the hotkeys used in Defense Task Force. They’re simple and easy to remember.
Navigate on the map with WASD, alternatively you can reassign this to the Arrow Keys & rotate your view with Q & E
Towers use the hotkeys located from 1 to 0, with the machine gun tower starting at 1 and the sniper tower ending on 0.
Increasing or decreasing the game speed can be down with Page Up & Page Down