I think one should be carefull about not bagging all issues together.
I see three issues related to travel in ED that could use improvements and rework, for different reasons.
1) Coop play setup. Herding the cats is no fun, so to speak. I would suggest a simple (and limited change) :
1a) Upon login in the game you may pick any owned ship without cargo.
1b) Then, said ship can be spawn in any spaceport where you have a ship or a friend present in the system. The spawn may not be more than 200 lyr away from your last spawn.
2) Boring SC. Here the problem is that SC flying is awfully boring, save the times where one does clever mass lock dodge and/or gravity braking. Now, the problem here IMO is the lack of terrain to play with, especially over long hauls. Maybe having a SC "safety off" drive mode where acceleration and top speeds are higher, but SC space time becomes dangerous (SC anomalies that may slow you down, or that you may use to slingshot) could spice long hauls. All I will say is that despite liking the slow pace of exploration, I despise the 20-30min SC to get to secondary stars. Maybe following chains of SC anomalies lead you to some deep space anomalies, not unlike the notable stellar phenomenon.
IMO short cutting SC with mini-jumps is more of a cop-out than a true improvement. SC could be made cool. So would interdictions if instead of the mini-game it was about navigating the SC terrain with no safety net while sticking/losing the opposing ship.
3) Lacklustre Pathfinding in Exploration. Making the galaxy a maximally connected graph in term of Hyperspace lanes has nipped in the bud the chances of a pathfinding / route paving Exploration gameplay. Maybe restricting the existance of hyperspace lanes based one the bodies types and mass could make the game more interesting. Especially if players could drop nav beacons that ensure the existance of lanes between them and boost the number of conections from the considered system.
Case in point is the Formidine rift pre-engineering : finding crossing paths was a very fun experience, that got destroyed with engineering. Having hard to get places should be much more common and route pathing could be a way to make exploration more meaningfull and lead to nice player driven content.
Final case : The sense of scale (invoked to defend super long SC times). It makes not sense to me since said long SC travels are optional. Which is an other way of saying that the sense of scale is optional. Which is an other way of saying that the game does a poor job of conveying said sense of scale. Then what is the point again ? Scale is best felt during exploration when trying to reach far out stars and trying not to get lost or stuck from a mistake. SC ? It's like 2h of highway driving, it's mainly boring.