I loved how The Expanse handled high speed turn and burn in space.

Fuck Syfy.

Economy cars don't have a lot of spare horse power and the AC isn't free to run. Combine that with poor maintain, that's even less to work with. I can't tell you how many otherwise technical people I know who don't think to change their engine's air filter.

It only gets them an hour of propulsion at one-quarter impulse thrust.

Which is basically classical atomic sublight rocket tech.
So some additional ability to just coast between planets when you are already in a star system.

Exactly.
Not only is the power requirement pretty low in comparison, but the system should also show a really sluggish response, especially when considering the sheer air volume of the Enterprise.
Biggest issue would probably be heat buildup after some time

I don't actually think that the scrap yard is a better place than your home/where you parked it. At least I hope for your sake it isn't 😄

The Picard Last Resort

Another good example on how bad the actual details of the science are in most of Star Trek.
Warp moves you by compressing the space in front of the ship and stretching it behind it.
Your frame of reference in the middle of it stays at rest.
So no stains on the wall.
Impulse power would be a completely different thing, though.
But even that the writers managed to get wrong most of the time, treating it like a kind of fixed absolute speed that you achieve, like the max speed of a car, instead of the steady acceleration capability it actually is, with no max speed besides relativistic limits.

Not watching Star Trek for the scientific accuracy.

And even the Expanse has some instances of bad and/or hard to believe space tech depictions, probably mainly due to production cost restrictions.
Take the whole bridge design of the Rosinante for example, with its gaming chairs or whatever acting as high-g-chairs. Sure...

So, you will always have almost always to engage that "I want to believe" mode.

For another more TNG contemporary show with mostly credible science, I can also strongly recommend Babylon 5 (which feels like a kind of predecessors to the Expanse).

I sold it to a family member for scrap parts. His son had a similar model.

Divert all power from inertial dampers to evasive manevers!

splat

Do they ever say how big the computer is in the show?

the Enterprise-D computer? A computer core was the size of a seven-story apartment block, and there were three cores.