Yeah, if you accept there is no absolute frame of reference, then you can get rid of the third person observer, and achieve a finer resolution in simulation.
If you imagine that fleets coming into combat are more or less matching velocity, then you can posit that maneuverability is more important as fleets close. Why? Because... um... they fire volleys at standoff ranges! Yeah! They crank up those nanofabs and pump out the shells and missiles or focus the laser arrays from several ships like magnifying glass against an ant... yeah! So you have to redirect power to maneuvering thrusters as you close range to make those kinds of volleys less effective!
So getting to the bottom of the map is essentially building up comparative velocity to the point where the enemy can't really focus on you... and then you can go full thrust while evading any counterfire.
At least it explains how harassing works... they're firing volleys into the path of your ships. It makes you burn harder to change course and evade, but they also give up achieving the acceleration necessary to actually catch you...
So you would have a less broad area of retreat if you had the ellipse, because you would be retreating toward a much smaller arc at the bottom of the ellipse, but your ships would be gathering together instead of splitting apart like in the current map that makes retreating so disastrous. Because they're aligning to an escape vector. They would technically be closer to each other than the enemy as they built up speed.