The idea works with the premise is that within space, there's a strange web-like lattice of lines. These lines can be traversed with something that for the sake of clarity, we'll call a line-rider.
One can only hop into a 'line' via a hub, a hub is a point in space where ten or more lines intersect, creating a stable point to enter into or drop from. One plots out their line path on a navigational computer, heads to the nearest hub and then uses the linereader to hop onto a line.
When in a line, one travels at what might externally be considered to be FTL speeds, but the actual speed is distorted within--err... linespace (that'll do). When travelling a line, occasionally other lines will intersect, so the player has to keep their ship as close to the center of a line (which is tunnel-like) as possible, as otherwise they'll find themselves being sucked off down into another line.
Lines also tend to have 'directional forces' akin to winds, so one line might be strong, whereas another might be weak, and it might only be possible to travel down certain lines in one direction on occasion. However, these winds are 'estimated' by the travel computer, so mostly the player will be able to plot out a successful course.
Those winds can change though, however rarely, so that the player finds themselves travelling down certain lines particularly slowly, or they'll find a line along their route 'blocked off' to them, so they'll have to either quickly decide upon another path (we'll get to that in a moment) or head for the nearest hub to plot things out again.
When in 'linespace', the player will have a minimap, and their route will be highlighted on the lattice, the map can be zoomed in and out. If a line on the map is red then it means that the line has become inaccessible along the player's current trajectory due to winds. The player can use this minimap to make course adjustements if nessescary and try to get back to their original path.
So basically, if you've ever seen Stargate with wormhole travel, it's similar to that, and the ship travels down a tunnel and there are endless intersections off those tunnels. The end result is a bit like driving down everyday motorways (with a great many more turn-offs and 'roundabouts' (the hubs) and sailing).
So basically, let's say one was following their route, and driving along down a line until the line split in two. They might originally have taken the left line, but the wind-forces of 'linespace' have stopped them from doing this, so they have to fork off to the right and try to make their way back to their original pathway.
I think I've explained this well enough now, and the end result really is a driving game. The problem with space I find is that it's too open and there's not much structure to allow for this kind of thing, and I think that this might be a possible solution, or it might be a terrible idea. I honestly don't know, and my lack of confidence in it tells me it might be a bit too unwieldly to work into a game.
It'd be fun though. Just think, in hubs you could have space stations near enough to planets, and these stations could work as 'bus stops', you could then have large carrier ships who'd travel the lines and ferry people back and forth between the planets. With such a system, a player could even take up the intrepid role of a Spacebus driver, in Space! ...sorry.
Anyway, these stations might be close enough to planets for either normal travel or perhaps some kind of slightshot system could be put in place, where a temporary line could be created to swing the player off at great speed for a very short time in order to reach a planet.
So you might have some hubs right next to planets, and some with stations that can perform slingshots to the planet (with a slingshot structure in the planet's orbit too, in order to get back). Aside from that, there might be a great many 'empty' hubs which aren't near planets, and even uncharted hubs.
So players could wander around and seek out things in these unknown hubs. Basically, missions could involve either travelling to hubs with systems nearby to fight pirates, or heading into unknown hubs to take out pirate bases, or simply as part of an exploration expedition. It could even involve ferrying goods, trading, or as I said, taking up the role of a bus driver.
Just think, you're riding the lines randomly (without having plotted a path), and seeking out new hubs, and you find a wrecked alien hulk. Perhaps the result of some ancient civilisation which tried to master line-riding and failed, it could have unknown and rather advanced technology on board, which could be sold to government researchers or black market bidders (rebels/pirates/et cetera).
At the end of the day, I can't help but feel that yes, this would be a lot like games that have jumpgates between systems, but I think the rationalisation here is more interesting, given that the hubs can be seen on some sort of line-map, and that there'd be uncharted hubs with random content in them and such. And moreover, travelling would still be manual to a degree, even though the player is moving between systems.
It's an idea, anyway, to avoid the tedium of usual interstellar travel. The technobabble though? That I'll leave to someone better equipped!