The logic I use when playing the game in respect to speed an
M = metres (obviously most man made space objects should be measured in respect to this scale)
K = Kilo or ‘000 (so when a distance is reported as 19.5 then I deduce this is 19,500 kms
Speed is also a measure in K so 80 is representational of 80,000 kph and cruise is approx 300,000 kph (the Space Shuttle circling the earth travels at approx 17,600 kph so a few centuries in the future should give us fusion engines and a 60,000 kph speed increase (Incidentally Deep Space 1 with it’s Ion Drive got to 180,000 kph after 3 months thrusting).
Lanes at 1000 speed are a 1,000,000 kph etc
None of these speeds are near relative light speed at 300,000 kps.
As to targeting at objects travelling at 80,000 each in combat – well add advanced targeting and like velocities when tailing etc means you just have to be a bit frugal with reality.