There are some small aspects of Open Space i would like to see upgraded.
The fuel indicator is one aspect that kept bugging me but it’s totally irrelevant to most people. My suggestion would be to change the HUD icon of fuel cells in space as well as the fuel indicator in the lower right corner to something more suitable, reactor-like indicator. Also, the fuel should be shown as a real number and not in percentage, thus, making bigger ships have a bigger tank and (maybe) consumption and smaller ships a smaller tank with smaller consumption. While collecting fuel, ships get proportional fuel to their tank capacity like 25-50%. It would make the arcade-ish collecting and spend more visually attractive and closer to realistic stuff with minimal change.
Gates and gate jumps could have some sort of animation or at least a bright flash of light making people disappear and reappear in a more fancy way than usual  While gates deserve some sort of re-design since they are a bit old by now, the loading screens could also change from 2D to 3D depending how “heavy” that change could impact loading times. But the flashy zap from one gate to another is also something very minimal in terms of work to do.
The Undock Button is more like a surprise button than a completely different and huge mode indication button. It deserves it’s place right underneath the HUGE PVP and PVE and COOP buttons. Nothing changed much from the first day i started the game and discovered the mode. I was completely unaware of that mode and the button representing anything i might be interested in. To this day people, newcomers mostly, are oblivious to what that button does because at first glance, it doesn’t look like something of interest.