A note on coleoptric nacelles.
Coleoptric nacelle designs, those shaped like an annular ring circumscribing the vessel perpendicular to the direction of travel (z-axis), can be thought of in two ways, both seem similarly useful. The first to imagine a single nacelle that has been expanded radially and contracted linearly compared the z-axis. The second is to imagine a single nacelle that has been bent into a torus around the ships hull.
Either way, there are some interesting repercussions. The first are geometrical in nature. The coils are spread over a larger volume. This would indicate that the same amount of energy impinged upon a coleoptric coil would be spread over a larger area, which might mean the segments could be thinner for the same warp material being driven at the same warp factor. This would explain why they would have a longer lifespan and faster acceleration compared to more normal coils. It would also imply a tighter turning radius and overall better warp maneuverability as well as a more touchy nacelle that is more susceptible to external influences. However, the simpler geometry would tend to simplify warp geometry calculations.
Even with thinner segments, the total coil volume seems so much larger that it would likely be more resource intensive to build. And with large outer circumference, it would seem the plasma conduits would have to be of a higher caliber, further intensifying material use. All that mass expanded that broadly would extract a heavy toll on impulse maneuverability as well. Of course, the Vulcan tendency for long slender hulls would allow for high torque maneuvering thrusters far fore and aft, negating this disadvantage.
The Vulcan needle-like hull indicates the warp field created by coleoptric nacelles tends to make fields of very low z-axis compression with a small x-y profile. Under the rules previously expressed, this would indicate high peak-transition efficiency and low integer efficiency. (This is the opposite of that expressed in the nacelle side-note above.)
other notes whenever I have the time. For the moment let me say simply: nicely logical.