The ship design is for ahem less than capitol ship sizes think more like BK 2
2nd ed than book 5 and nothing at all like T4 FF&S.
Jump, and Hop drive is powered by "collectors", Fusion, or Antimatter.
Skip drives add fission to the mix, though you could house rule that a Fission 10 could power a Hop 1 (without the overclocking and excessive fuel use BTW).
And then you have the TL stage effects you could have a Jump Drive Experimental model show up at TL 7 allowing a fractional efficiency and poor reliability or you have the ultimate expression of Jump 1 drives at TL 12 producing 1.3 times the normal output for a drive that size with exceptional reliability and quality and better fuel use.
So you have extra variables to concider when putting together a ship.
That J1 M1 200 ton free trader can be a TL 12 ultimate in everything and be a great little ship with more cargo space no engine problems and so forth.
Or it could have been put together at TL 8 using prototype designs and experimental equipment lashed together with bailing wire and spit and the engineer is a leading theroist on jump space, and has seen raw jump space perhaps a half a dozen times too many.
The more space you give the crew the better their morale and + DM's on Sanity checks, less space than standard... hoo boy the GM is gonna have fun pushing your buttons.