That is an interesting question.
This is not a complete list.
- Upgraded, deeper gameplay mechanics : bounty hunting, piracy.
- A more versatile implementation of the PowerPlay infrastructure. The Power territories could be used for so much more than just a multiplayer territorial game. It could be used to give the game more depth on all levels of gameplay.
- Planetary mining. I would like specialized mining SRV.
- More SRV types: I already mentioned mining SRV's, but also heavy combat SRV, a cargo SRV, perhaps some kind of hoovering SRV (like the drones), a submersible srv for future planets with water bodies.
- A better planetary navigation system.
- A better/more interesting way to get info on planets: being able to do scans from space to locate a general area where to find materials, or planetary mining locations and then go down to the surface and do the pinpointing and mining with an SRV.
- Access to atmospheric planets with flora and fauna, and the upper layers of gas giants. and volcanic planets etc.
- Alliance ship designs
- More ships in general. Everybody wants more ships in general. It is never enough

.
- True Imperial and perhaps also Alliance space station designs. I think this is necessary to make occupied space feel less uniform.
- More NPC military capital ships like destroyers, Frigates, battleships, dreadnaughts, military tankers etc. I would like to see NPC military move in small fleets, strike groups, squadrons (compare the X-wing/TIE-fighter games, that felt very realistic, very naval).
- I look forward to being able to walk around my ship and do space walks, but it is not a high priority
- More life in space stations: npc walking around in the docking cylinder and hangar. NPC driving around on planet surfaces and in planetary settlements
- More piloting action in Supercruise. I already made proposals about that.
- I also would like the HUD to change in supercruise, comparable to the way it changes on planetary approach.
- Ingame tools to solve ingame problems. Less reliance on external websites: A comprehensive multipage information screen (compare the powerplay screens) about the engineers for example. An ingame shipbuilder comparable to the external shipbuilder websites.
- All blue prints to be visible and pinnable at any time of any engineer we have gotten access to. The way it works now is unnecessary inconvenient.
- Shuttles for big ships. So big ship owners can at least got to a small station to pay of fines, deliver parcels, or a few passengers etc.
- More tools to interact with stuff, like alien objects. Currently it is scanning or shooting. That is too limited. For example taking samples.
- Scientific modules. We might do research on atmospheric planets, take scientists with us etc.
- An NPC crew system. I have made several proposals to make this work.
- Winging up with NPC, which should make it possible to do protection/escort missions. A NPC trader might ask me to wing up with him for a while and protect him.
- Offline mode would be necessary to ensure I can keep playing Elite for many years to come
I for one am glad that will never happen. I have been there with Frontier: Elite II and combat was horrible.
And a toggle mode would be totally unpractical to implement. So... no, it won't happen.