[Andrés]

Mov/Ton of all engines

Standard:
Name

Ion Engine
Tonnage: 10
Movs: 1
Ratio: 0.1

Contra - Terrene Engine
Tonnage: 10
Movs: 1
Ratio: 0.1
+ 1 bonus

Jacketed - Photon Engine
Tonnage: 10
Movs: 1
Ratio: 0.1
+ 2 bonus

Quantum Engine
Tonnage: 10
Movs: 1
Ratio: 0.1
+ 3 bonus

B5 Fission:
Size: Light - Medium - Heavy - Huge
Ton: 10 - 60 - 100 - 200
Mov: 1 - 7 - 12 - 25
Ratio: 0.1 - 0.116666667 - 0.12 - 0.125

B5 Fusion:
Size: Light - Medium - Heavy - Huge
Ton: 5 - 30 - 50 - 100
Mov: 1 - 7 - 12 - 25
Ratio: 0.2 - 0.233333333 - 0.24 - 0.25

B5 Anti-Matter:
Size: Light - Medium - Heavy - Huge
Ton: 5 - 30 - 50 - 100
Mov: 1 - 7 - 12 - 25
Ratio: 0.2 - 0.233333333 - 0.24 - 0.25
+1 bonus

B5 Gravimetric:
Size: Light - Medium - Heavy - Huge
Ton: 5 - 30 - 50 - 100
Mov: 1 - 7 - 12 - 25
Ratio: 0.2 - 0.233333333 - 0.24 - 0.25
+1 bonus

(most advanced engine of each tech gets a little smaller size and a slightly increment in ratio)

So basically all B5 engines come in these "mounts"
Mount - Ton/Cost/Sup - Movs
Light - 1x - 1x
Medium - 6x - 7x
Heavy - 10x - 12x
Huge - 20x - 25x

I'll add a new scale called Massive (50x - 80x) but I'll have to be careful not to pass the 255 movs limit (before dividing by the eng per move).
That's really a bad restriction to newtonian movements in really big ships.

My idea of SW
Atomic Drives
Size: Light - Heavy - Massive
Ton: 12 - 120 - 600
Mov: 1 - 12 - 80
Ratio: 0.083333333 - 0.1 - 0.133333333

Implosion Drives
Size: Light - Heavy - Massive
Ton: 10 - 100 - 500
Mov: 1 - 13 - 85
Ratio: 0.1 - 0.13 - 0.17
(Ratios are lower than HKID, but since max engines are by number not % you can get higher final speed, supply consume will also be very high)

HK Ion Drives
Size: Light - Heavy - Massive
Ton: 8 - 80 - 400
Mov: 1 - 12 - 80
Ratio: 0.125 - 0.15 - 0.2

So I hope this explains my original point with numbers.
I made HK Ion Drives slightly better than standard ION ENGINES, and I'm also too close to the maximun limit to make them any better.
I can't show progress in propulsion if I make SW atomic drives == B5 fission engines

As I see it we have to option.
Make B5 fission engines worse (are they supposed to be primitive anyway?)
Or forget about this little idea of making similar techs have similar performance.

BTW gravity manipulation hasn't been left behind in starwars, Repulsorlifts (anti-grav engines) are still very used and the best choice within a planet. They are used not only by ships but also by land speeders atmospheric fighters, and droids. I didn't mention them because they'd have no use in SE IV. Interdictors can project planet sized gravity wells, and tractor beams operate with a combination of gravitic and magnetic pull.