Well, essentially, for in-system Hyperdrives. we'd have to have a new hyperlimit system.
Suggestion:Have one from the Star, 1 Au per solar mass (based on our home system), and maybe a million kilometers per [planet size (how ever we define that)]^1.1.
The ^1.1 is meant to result in low values on small planets, so that we can cut off and abstract away; A large Jupiter-like body with two dozen moons would only have one hyperlimit assigned to it.
Thus, movement would be relatively slow near planets, but one could cruise faster in between; The inter system would be more secure due to the stars hyperlimit.
Maybe, a ^0.95 on the stars limit would result in bigger stars with huge systems not having an equally huge limit.
But that would have to be done drastically different from Aurora is the actual hyper-system.
Either, we require ships to have a jump engine, then it could just be a modified engine that allows a speed boost for low, ongoing fuel consumption, only in system outside of the "inner" hyperlimits.
The speed boost shouldn't be a flat x10, it should maybe start at x2 and then increase by 0.5 or 1 with every advancement of Hyper-Jump technology.
We could also go the way of having special thrusters, this would allow us to specify a minimum size and maximum size efficiency, where ships get a speedbost based on how large they are compared to their thruster array.
I can see a combination of both, where small defensive ships get a small hyper-thruster and thus have no need for a larger jump engine.
As for the fuel efficiency, I think it's ok to start higher than what we have today, because in this case, with a bit of handwavium in place, we can go for gameplay concerns as well.
Once it takes a month of acceleration to reach the projected lethal speeds we try to avoid, we don't need to ramp up the fuel consumption any further, even if that still means a silly high fuel efficiency; as much as I love logistics, that might be a bit much.
Maybe, higher level engines should give less extra output, and more bonus to efficiency, with less cost ramp up than we are used to by Aurora.
/rant