Ok, so Impulse, Cruise, Sprint are all sublight ship speeds,
with the only warp speed being the Hyper, correct?
Yes - though note that Cruise, Sprint, and Hyper speed can all be limited by available power.
Turn Rate = [(number of directional thrusters)*(directional thruster thrust rating)*115/(total size of ship)] + 6
Ship Speed = [(number of main thrust components)*(thrust per main thrust component)/(total ship size)]*X
X = min( 1, (reactor excess output)/[(number of main thrust components)*(thrust level energy use)] )
Hyper Speed = (hyperdrive's rated hyper speed)*X
X = min( 1, (reactor excess output)/(hyperdrive's rated energy requirement) )
accelerationRate = ((topSpeed / 8) + 0.5) * accelerationFactor
accelerationFactor = ((reactorPowerOutput - staticEnergyConstumption) / engineMaximumPower)
if accelerationFactor > 1
accelerationFactor = min(2, accelerationFactor^025)
Hyperdrive stacking: A design with two different hyperdrive components (i.e. Kaldos + Equinox, not Kaldos + Kaldos) will result in a design which effectively has a single hyperdrive with the following characteristics:
1. The hyperspeed energy requirement will be equal to the maximum energy requirement of any hyperdrive component carried by the ship.
2. The time required to initiate a jump will be equal to the minimum jump initiation time of all the hyperdrive components carried by the ship.
3. The hyperspeed will be equal to the maximum hyperspeed of the hyperdrives carried by the ship.
4. The size requirement of the effective hyperdrive, as you might expect, is equal to the sum of the sizes of the hyperdrive components carried.
Possible name-changes like Impulse, Sublight, Maneuver, Warp
might make these more easily recognisable from a Star Trek perspective...
At least for the Star Trek with which I am familiar - most of DS9, TNG, and VOY; some of ENT; and a bit of TOS - Impulse and Sublight are mostly equivalent while Maneuver is essentially meaningless as a speed term. Maybe Quarter/Half/Full Impulse for the current Impulse/Cruise/Sprint, if you wanted to do a bit of Star Trek flavoring for a personal mod.
Also, the Impulse speed seems to be fixed at 3, regardless of all types of engine components.
Is there any way to increase Impulse speed through engine technology,
or barring that, to modify the base speed, even though it will be fixed?
I am not aware of any way to change the default Impulse speed.