Amazing! Glad you tried your hand at optimizing it.
What's missing is being able to see the movement of the ship relative to a specific planet/moon. That would make it much easier to work with the orbits to touch the moons.
DeltaV is not the name of the fuel, it's a real metric that is used to measure by how much the ship can still change its speed. Delta means difference, and V means speed.
In a ship, Delta-V is to fuel what the distance autonomy is to fuel in a car. But because nothing is there to stop the ship, the distance is infinite. What matters is being able to control where the ship goes, hence the Delta-V metric.
My game is not really accessible to people that haven't played Kerbal Space Program sadly. I need to build a tutorial!