Various techs on the tech tree are dependent on others unlocking first. Currently they're just lines connecting one to the other, so what I'd like to see is little triangles added to the lines to indicate direction, doesn't have to be anything fancy to show that both Tech A leads to Tech B. In the included image, for example, I hadn't realized the Droid Core Facility needed the input of the techs off-screen, having recently played an automation game where the tech tree sprawled every which way rather than flowed to the right like in Modulus.