This is really clean work!
I am most impressed with how tight your fit of the parts is. Does the kit assemble well?
Just to drop in on the bridge questions; the angled bridge was never actually cannon, nor approved by Roddenberry. It was accepted by many because of when, and how, it was speculated.
If you look at the diagrams where it was first proposed, the angled bridge was introduced by Franz Joseph, after the series was cancelled and Star Trek, thought dead and never returning. The idea came from the design observation, that the small pod on the back of the bridge module, was "the" turbo lift. He included this idea in his technical manual and much beloved blueprints. Since he did contribute to the show, most clearly the Animated Series, he's credited with asserting canon-fact.
However, that was never affirmed.
Actually, if you look at the angled proposal, it assumes that the bridge takes up the entire outer hull housing. If you measure it out, there is a lot of room in the outer bridge module housing, and even the exterior detail on the filing model, to suggest that the bridge set is nestled into a housing with a decent sized-corridor area around the set-area seen on the show. The turbo was at an angle on the set, but that didn't prove that the turbo shaft was at the stern of the bridge module. It could have been set at a clean axis, with the turbo car slipping up from below, within the outer hull shell.it was suggested that extra turbo cars were housed in the cylindrical nodule at the back of the bridge. The extra cars could move forward, into the circular housing around the bridge, and circle into position when the car at the bridge access point was used. This would permit the main turbo shaft to rise to the side of the rear-bridge, with extra cars, for quick access for exits into follow-up cars; those stored in the cylindrical area. Such a quick replacement of the cars was seen in several episodes, where the turbo car was immediately available, after someone had exited. There was little time for a replacement car to rise and replace the one that had been used.
FYI; the missing bathroom, so often speculated about, was also suggested in this outer area, toward there front of the "shell" and access from the monitoring stations near the front of the bridge. This was affirmed during the Animated series.
As for why Starfleet placed bridge modules in the top of their ships, in a area seen by many as exposed, was for a desired design-value, beyond dramatic visuals. Mr. Roddenberry wanted the ships to be realistic and relatable to engineers and scientists. He sought out the advice from Asimov and other science-credible writers. Matt Jeffires encouraged the proposal that starships were module and that major sections could be replaced or refitted at staircases, for efficiency and to encourage the longevity of a design. Recall, he was very familiar with aircraft proposals.
The Constitution class was not supposed to be seen as a simple, stagnant vehicle, but an older ship, by the time of the series, with a history before the episodes of the Enterprise were shown. It was proposed to be modular and interchangeable (as represented in several bridge graphics at the engineering station, and in the graphic by the turbo shaft) which was upgraded and improved as technology progressed. The main computer, housed below the main bridge, was supposed to be removable, easily, at a space dock, as was the set of nacelles and even the whole primary hull from the secondary hull. The ship was modular and designed for continuous replacement of essential components. It was even proposed that the nacelles would be swapped out during refits throughout its life, instead of having major engine overhauls that would dock the ship for months.
Replacing the main computer would require replacing the bridge as well, as that room was the main interface to it, with the rest of the ship supporting the bridge commands. From a military position, the bridge is very much exposed, but the Constitution class was intended for far more than military operations; it was involved in colonization, merchant support, scouting duties, and a wide range of scientific missions. Computer systems would require frequent upgrades for varied scientific duties and even customisation, as mission needs required. Upgrading and refitting a modular vessel, even if it would provide a potential vulnerability in a small part of its purpose (military duties), was considered a reasonable trade-off to quicker refit periods.
You might be interested in the speculation, around the sets of both the original and Next Generation series, was that the bridge also could be ejected as its own life support module. There were script suggestions to include this in episodes (Doomsday Machine & The Ultimate Computer), but like the separation of primary/secondary hull along the interconnecting dorsal, hard to fit into a TV budget.
The Klingons followed this design plan for the same reasons, and in fact, had copied much of the federation designs, but the Romulans were never established as having bridges positioned at the tops of their TOS vessels.. Their bridge location was never identified as at the top of a ship, and in fact, it was so small, its location remained a mystery in canon.
