Great Topic!  Thanks for giving us the opportunity to give you some input cricket.

In Starfleet battles (I'm not so familiar with the newer Federation Commander) the speed ships could attain was a complex relation of how much warp power they had and how much they were willing to dedicate to just movement.  Trying to port that over to another game would be painful at best.  However the extreme cases should probably be considered (e.g frieghters on the low power end and fast cruisers on the high end). 

Perhaps though the more pressing issue is maneuverability.  SFB (and I believe FC) ships have turn modes.  This is generally related to the class of the ship, but varies from race to race.  I think this is actually the most important aspect of movement to capture, given that most warships had similar speed limits.

So here's my two proposals:

1) Base thrust on turn mode
This should be quite straight forward since all the SSD's clearly list the turn mode:

Mode Thrust
F         2
E         3
D         4
C         5
B         6
A         7
AA       8

Ships with lots of spare warp power (e.g. fast cruisers or X-ships) should get some bonus thrust.  Ships that have less warp power than they need to go "full speed"  (e.g. monitors, frieghters, tugs - but not battleships or dreadnoughts) should get a bit of a penalty on thrust.

This would give a Fed CA a thrust of 4 and a Klingon D7 a thrust of 6 - which I think speak well to their relative turning ability.

Any ship listed as "Agile" should probably get overthrusters.  I wouldn't want overthrusters to be a really common thing on ships.

2) Add new Ship Traits for Maneuverability

Definitely a more complicated option as it requires coming up with sensible new traits AND finding an appropriate cost for them.  If this could be pulled off then I'd have some much different "thrust" suggestions - probably based on the ratio of warp power vs. warp movement cost - which would actually land most of the fighting ships in about the same area - but with some exceptions (e.g. new Romulan "hawk" series ships have lots more power than the original "eagle" series ships).

-Tim

Okay, had some more thoughts.  Without complicating life too much, this would work within the current system:

Base Thrust
Battleships and Dreadnoughts: Thrust 4
Cruisers of all types: Thrust 5
Destroyers and Lighter: Thrust 6

Take base thrust and modify by turn mode and warp power

Turn Mode
If a ship has poor turning in SFB (Turn mode E or worse) then -1 thrust
If a ship has good turning in SFB (Turn mode B or better) then +1 thrust

Warp Power based on SFB stats
If a ship has enough warp to generate 30 movement then no modifier
If a ship has enough warp to generate more than 30 movement +1 thrust (e.g. some war cruisers, most romulan "hawk" ships)
If a ship has enough warp to generate significantly more than 30 points +2 thrust (e.g. fast cruisers, raiding dreadnoughts, x-ships etc).
If a ship has less warp than is required to move 30 then -1 modifier (e.g. romulan war eagle)
If a ship has significantly less warp than is required to move 30 than -2 (e.g. freighters, monitors etc)

@Madpax - I agree with you, although I think the issue lies more with balancing firepower and defenses than with thrust - and to be honest I think the weapons are probably already "locked in" so it would be more a matter of just increasing the relative defenses and/or hull points of ships to compensate.

-Tim

I've tried out both using thrust based on size (and then modified for warp power and turn mode) and also thrust based on turn mode (and then modified by warp power).

I have to say the turn mode one "feels" better.  I have to double check some numbers and then I'll post some examples.  I think one reason it feels better is because the turn mode already has the "size" of the ship accounted for.

Dan I know you aren't big on a D7 being faster than a constitution class - but as I see it there really is not upper limit on "speed" with the starmada movement system - if anything speeds become unpractically high quite fast.  If you want to maneuver you have to stay near your thrust mode in speed - and thus turn mode!

EDIT:
Here's some samples:
Fed CA: 5
Klingon D7: 7
Fed FFG: 8
Kzinit DN: 4
Fed CL: 6
Fed NCL: 7
Fed CF: 7
Fed DW: 7
Orion Light Raider: 10
Kzinti Frigate: 9
Rom Battle Hawk: 4
Rom Skyhawk: 8
Rom King Eagle: 5
Rom Fire Hawk: 6
Free Trader: 5
Small Freighter: 4
Large Freighter: 3
Heavy Freighter: 2

Based on "Turn mode" and then warp ratio and a misc bonus.  If warp ratio is 36 or more +1, if its less than 30 -1 and if its less than 20 -2.  Misc bonuses are for "dedicated fast ships" +1 and nimble +1.  I decided the CFs need a higher bonus than just based on warp to make them interesting.  The logic being they have less heavy weapons so more available power to engines as opposed to the war cruisers/raiding DN's/frigates that all have high warp ratios but still are packing their full compliment of heavy weapons. 

Edit 2: Okay, can't figure out how to do attachments in PM's so here's the spreadsheet with all the thrusts based on the method above.

Okay, good point.  What do you think of the thrust ratings I posted above?  The "average" value for heavy cruisers (kind of the mainstay of the SFU) is 6.  I think that's decently fast don't you?  The lowest I have for a fighting ship is 3 for the Fed/Gorn Battleships (which aren't even in Klingon/Romulan Armada) and the fastest is 10 (Orion Light Raider). 

-Tim

My SFB SSD's show the Romulan Snipe and Orion Light Raider as nimble.  Not sure if this designation made it into FC or not.

If you are going to give them overthrusters, perhaps reduce their thrust by 1 as I added a bonus thrust to them for the nimbleness.

Also, I am pretty sure that the Romulan Nuclear Space Mines didn't make it into FC.  But I gotta say they were cool and would help the "eagles" be a more distinct class - plus you have mine rules in SNE - so wouldn't be tough to add.  The snipe, battle hawk, war eagle and king eagle all had one NSM.

-Tim