If you increase the range values by 1000 then that 200km diameter planet suddenly becomes, 200,000 km, which would make it about the size of Jupiter (which has a diameter of 146,000km) which is then fine.
Asteriods measure in the 200km diameter range, not planets.
This is a MMO, not Physics Class. Obviously a 24th Century Vessel would not engage at a maximum range of 10km. Now would sensors need to be within 15km. Frankly I have always ignored the numbers and pretended that they were much larger. It got easier once Impulse stopped being marked in kps on the UI.
Full impulse equals the speed of light and Warp 1. Thatīs why nobody flies at Warp 1, itīs not efficient. Obviously in STO the speed of full impulse is depending on your engine type. And i hope km does not mean kilometers, wasnīt the range of a photon torpedo like 2 million kilometers in the TNG era ?
the beam weapons, are basically lasers. Lasers break down quickly over distances. So a max range of 10km would be fairly accurate, if maybe a little long for beam weaponry. As for torpedoes, nobody would use phasers if the torps could hit at 10 times the range. I'm guessing the torps have minimal amounts of fuel for guidance in order to maximise the yield. Meaning the farthest viable range for a torpedo to track and correct it's trajectory to hit it's target is conveniently also 10km.