Tyler wrote:What does shape have to do with its ability to function? Does a circular nacelle move slower than a triangular one? Does a grey hull have better defence than a white one? Does a set of pylons pointing to the side then up have greater durability than diagonal ones? Does an engineering hull split into two generate more power? Is a circular saucer more fragile than oval one?
Variations over time is one thing, what Starfleet does is excessive with no other explanation other than "We felt like it". Better yet, how does the exterior shape make the tech inside become weaker?
Sure, some of it is going to be based on aesthetics, but to humour you let's take each point in turn.
Circular nacelle vs oval vs triangular -- the nacelles contain the warp coils that are the core of the ship's interactions with subspace. Over time the shape of warp coil elements will likely have changed as research is done into subspace field generation and manipulation. Also, shape will also be driven by the need for space for additional machinery, especially for the Bussard ramscoops that are a common feature of modern nacelles. There is some reuse of nacelle design amongst various classes, though -- Enterprise (refit) and Constellation share a nacelle design, for example; as well as Galaxy and Nebula classes.
Grey hull vs white hull -- new hull plating alloys were pioneered in the Miranda class that allowed the elimination of the grey thermocoat that had been a feature of starships for decades. This development simplified ship construction by eliminating the complicated and painstaking application process.
Nacelle pylon shape -- while ever-stronger materials have been developed for use in spaceframe construction, ship size has increased and commensurately nacelle weight, too. Pylon geometry is based on engineering analysis of the static and dynamic stresses that result.
Catamaran engineering hulls -- in the NX class, the split hull was a way to give the spaceframe the desired rigidity under stress. For the Akira class, the design was intended to provide a "harbour" area as the ship recovers its fighter.
Now, stepping away from the in-universe perspective, you do see commonality between ships of the same generation. The Miranda, refit-Enterprise, Constellation, and Excelsior classes are all obviously from the same time. The Nebula and Galaxy classes are first cousins, while the Ambassador is a perfectly reasonable intermediate stage between the Excelsior and Galaxy classes. While the graphic artists who put the designs together wanted the ships to look good, they've also been quite conscious of how the designs would change according to era and role; the designs aren't as capricious as you make them out to be.
Any Fleet Ops Cheyenne model should be close to what has been seen on-screen, else it's not the Cheyenne class. I wouldn't object to a successor class model like the current Miranda II and Excelsior II, but an actual Cheyenne class should be the canon Cheyenne model.
As for the Prometheus ... that's been argued about at length elsewhere. Long story short, the devs hate section separation (saucer sep on Galaxy; MVAM on Prometheus). The Galaxy is an awesome ship regardless of whether or not separation is included; MVAM was sort of the Prometheus' main trick, and the devs deciding that they weren't going to bother with it doomed the ship to the obscurity of "map object" status (it's present but not properly implemented as of 3.2.7, although it does have a nice model). The devs haven't shown any interest in changing this status quo.
