i think its a bad idea to say every terran ship in the game should be blocky. theres actually
of variation in the terran ships, you have sleek ships like the Perseus and the herc2 are sleek and dont have anything square about them. you have hard angular ships like the the pegasus. the hecate isnt that blockey at all. and the deimos has some considerable curvyness. the only ships in freespace that are blocky were the ones from fs1 where the technology at the time wasnt capable of runing with high poly models.
also you have the whole ww2 analogy. you can sat the terran-vasudan war was an analog to ww1. the tech is new, neither side was familiar with spaceborn warfare. then you have the ww2 era where the shivans are coming it, were a little better at war in space and the technology advances (wile in terms of air combat the improvement between ww1 and ww2 was in engines and weapons, in freespace it was shields and weapons). then you can think of freespace 2 as the korea/nam/desert storm era combat. planes get faster, sleeker, and we have advancements in stealth, weapons and sensors. in freespace we also see the ships getting sleeker, a little faster, we get stealth, we get beams and flaks.
using that analogy you can say i aim to make ships from the current to ww3 era. we have the nebula and we have to contend with the fact that we know what the shivans could actually hit us with if they ever came back. so ships become sleeker to contend with nebular drag, also id like to display some trans-atmospheric characteristics (that means wings and curves). caps move faster and have more firepower condensed into a smaller hull. also theres more experimental tech being used. the maelstrom was going to be stealth but removed the stealth tag for balence reasons. both it and the phoenix use reverse-engineered shivan tech.
ive had better luck with shivan and vasudan ships as far as making them match the fs universe. one of the reasons behind my pirate fleet is because the game lacked one to begin with, and i could have some more artistic flexibility with the new ships. i could go retro on the weapons by re-introducing gatling guns, mines, ect. some of those ships are among my newest and best done. but must of my work in the last couple years has been mainly doing htl overhauls.