I know, I know; It's been suggested and shot down a million times before so I'll try to keep it short and to the point.
Supercruise would behave exactly the same way that it currently does with a few additions to its usefulness:
1.) If a player is currently in a star system and wants to leave that system via supercruise, the start-up procedure is no different than its current implementation. Once in supercruise, the player would simply fly until they've reached a predetermined point where the host star's "sphere of influence" ends.
- Concessions might be made for systems like Sol where the Voyager probes are still counted as being within the solar system despite being a gazillion miles away.
2.) Once the player reaches this point, they'll be shown a prompt similar to the one displayed when leaving planetary flight, letting them know that they're leaving the system. This message will also be used to mask the de-instancing/unloading of the current system and the player's transition to interstellar space.
Once in interstellar space, the player is free to fly in any direction; they're not required to select a destination system.
While traveling in interstellar space, star systems will have a visible ring/sphere (similar in appearance to orbital lines) denoting their sphere of influence.
The top speed of supercruise would be greatly increased while traveling in interstellar space, though it would still remain slower than jumping directly from system to system via hyperspace.
Fuel constraints still apply and would most likely be changed for balance.
3.) If a player traveling in interstellar space chooses to enter a system, regardless of having targeted that system, they'd simply fly into the system's "sphere of influence" and be shown another prompt indicating that they've entered the system similar to the Glide Mode indicator (which also masks the loading/instancing of the system).
Not needing to repeatedly jump from star to star on long journeys assuming you have the fuel.
Immersive and adds a seamless feel to long-distance travel.
Slower than jumping directly from system to system via hyperspace.
I'm sure there are others that will be pointed out to me.
Basically, this idea is taking supercruise and the transition that occurs between space/planetary flight and scaling them up to work with interstellar travel. It's meant to benefit players who desire a more immersive and seamless "space sim" experience who also don't enjoy stopping at every single star along their transit route.
What do you think? What changes would you make? What would you keep/throw away?