In modeling, most observers are 3-4 feet away from the scale model.
However, the work on STC is a bit more challenging in resolution than TOS had.
In reading about the original filming of the original series, it seems that sequences were filmed in 35 mm and then mastered for TV in NTSC standard definition.
In 1966, this was roughly 240 lines of resolution.
However, STC seems to be mastering in 1080 at 16:9 and then downscaling to fit the 4:3 aspect ratio of the original.
For this reason, it's actually more difficult for your team to recreate the original props and sets for filming in 1080. There is a real challenge for the STC crew to not have the sets distract from the story. Sometimes, even in high budget films, the props look artificial. In STC, the props are so accurate that they do not distract and instead draw the knowledgable viewer into the story.
In the context of 2K and 4K filming, the pixel depth begins to approach the limit of the human eye to perceive one pixel.
Presuming that the viewer is looking at an object 3 feet away, the limits of resolution discernable to a viewer could be roughtly the equivalent of 4K at maximum detail. However, since TOS was filmed in Standard Definition, the accuracy of specific items really only required light detail work. As the digital camera resolution has improved, the need to build additional detail is more significant.