So I just had a Jimmy Neutron Brain Blast, and if I'm right, it might solve several of the most odd-seeming details of Star Wars's hyperdrive technology (at least, to me).
It started with me watching Youtube, and getting a Short from Rebels about Thrawn trying to track the Ghost. And a question I always had is... why are they even at sublight for any of these pursuit scenes? During the Imperial Era, hyperspace tracking was a myth - why wouldn't the Ghost just stay at hyperspace all the way from point A to point B?
And then my brain made a Connection.
Because it has a class-2 hyperdrive.
One of the biggest things that's always bothered me about hyperdrive is the class number system - the lower the number, the faster the ship. The DS-1 had a highly class-4, a Venator has a class-1.0, the Falcon after Han was done with her had a class-0.5. And that has never made sense to me. But then I thought... "wait, what if it isn't their speed in hyperspace?"
Some Sci-Fi settings - notably Battletech and Battlestar Galactica - use FTL technology that moves the ship instantly... but then takes time to recharge. I'm not trying to say hyperspace is instant, mind, we know it isn't, but if a ship's speed in hyperspace is independent of the drive's class rating... what if it has something to do with its capacity to stay in hyperspace?
This would then explain hyperlanes, and why certain systems are important, and why you so often see ships like the Ghost or the Razor Crest or even entire fleets in normal space while traversing to a destination. Certain routes between systems in hyperspace are quicker, or slower, or smoother, or rougher, for a ship to go through - any ship - but based on how long they can stay in there, they have to stop a certain number of times to get from one place to another?
Let's use an example - Kuat and Coruscant are, galactically speaking, around the block from one another. Kuat builds and designs a lot of ships for Coruscant. So when you test a new ship's hyperdrive... you take it around the block. Drive it to Coruscant, get its paperwork done, all that good jazz. How much of its hyperdrive capacity does it expend to get there? If we're talking the Ghost, that would hypothetically be a two-jump trip - for the Death Star, it's four, for a Venator, it's one, and the Falcon could make it to Coruscant and back... on a single hyperdrive motivator charge.
Because yes, I think the hyperdrive motivator is the thing that determines this. Go back and watch Phantom Menace - once they determine that the motivator is damaged, they start bleeding power... and have to drop out of hyperspace sooner. What actually defines the relationship between motivator and hyperdrive rating could be any number of things - like, as an example, the relationship between the motivator and hyperdrive sizes and the overall mass of the vessel - still isn't clear (though I feel that's a good start, given that we've seen how big a Venator's hyperdrive is when Maul ripped one apart, compared to how small the Naboo ship's drive was)... but this theory would also explain one of the more commonly mocked lines from the very first movie.
"It's the ship that made the Kessel Run in less than 12 parsecs."
"bUt HaN, a pARseC iS A mEAsuRe of DisTanCe!"
While this theory explains the class rating, the class rating is still not quite perfect. Because it doesn't take into account... how fast the ship can recharge the motivator. Or, perhaps in terms of distance... how much space it has to cross before it can jump again. In current canon, the Kessel Run is said to be a 20-parsec hyperspace route through the Akkadese Maelstrom. Think about that statement in the context of the above. With that, we can surmise the following: Regardless of the jumps being made, most smuggler ships have to traverse about 20 parsecs of normal space along it. Han managed it in 12. If the Akkadese Maelstrom is a region that makes hyperspace rougher to traverse - such that the class rating is essentially irrelevant because of how fast you consume motivator charge to punch through it (think jumps like the Mantis made through the Koboh Abyss in Survivor; short, but so risky that you dare not make it a long one) - then the ability to recharge that motivator quickly is the deciding factor. All Han did was find a way to get his motivator back up 40% faster than any other ship. Especially given that in a lot of high-energy systems in the real world have thresholds of activation energy that are required to start a reaction, but the energy to maintain it afterward is significantly lower, so it may be called the hyperdrive motivator because the majority of its capacity is spent making the jump to hyperspace - after which, staying in takes less.
And that is why the Falcon is one of the fastest ships in the galaxy - not just because she can make longer jumps than almost anything else... but because she can jump more quickly along the sublight parts of the route. And because the class rating system doesn't account for that, bureaucratically-oriented or otherwise less tech-savvy people will be prone to underestimate her speed because they don't know what makes her special. Immediately, Luke's skepticism makes sense - he's worked on speeders, sure, but as a moisture farmer, I doubt he had an academy-level education in hyperdrive mechanics.
With just a few detail connections, I think I may have finally managed to make more sense of hyperdrive technology than any on-screen or novel (even Legends) has ever attempted.
"Why is a hyperdrive motivator so important that you need to replace the whole drive?"
"Why is Han using a measurement of distance for speed?"
"Why does lower number mean faster ship?"
"Taken separately, they mean nothing, but together..."
[...]
"A pity you do not study art, Agent Kallus. There is much it can show you, if you know where to look."