Heya! Yeah the colour backgrounds were a placeholder to more easily distinguish which upgrade effected which employee type. We ran out of time to replace them. This will be touched up in a future patch after the Ludum Dare is over!
Good point about the speed. I figured x2 speed and 1/2xDuration should be equivalent. Will reconsider that. The main UI still need a lot of work anyways.
Thank you for the feedback!