Even assuming that regular ships travel at a greatly reduced speed compared to the Millennium Falcon: how can the human body (Jedi/Sith or otherwise), along with any items not strapped down withstand the deceleration of the ship without flying through the front of the ship or being dashed against the ship's walls?
This is addressed in (amongst others) the Star Wars: The Force Awakens - Incredible Cross Sections. Once a ship exits hyperspace, the crew experience a considerable de-acceleration. The ship's "Acceleration Compensators" deal with this.
You might wish to note that hyperspace is described as being a *"different dimension" (one where the speed of light is presumably much higher) so the acceleration/de-acceleration spike is rather lower than you might think.
Since I'm by no means an expert on this, I'm just going to refer you to here for the answer. Note the third picture in particular.
I think this is how most universes explain stuff like that, from what I recall. Most of the time they just say they compensate for rapid acceleration, and don't mention deceleration, but remember that deceleration is just negative acceleration, or acceleration backwards.
Although I'm always more of a fan of the MST3K explanation:
If you're wondering how he eats and breathes And other science facts, Just repeat to yourself "It's just a show, I should really just relax"