In the most basic sense, the rough shape and idea for a capsule-shaped lander came from von Braun's proposals for the Mars Excursion Module, that got fleshed out in the early 80s.
Of course, I envisioned this as being a much more sophisticated craft, with probably nuclear (or perhaps fusion) powered "plug nozzle" rockets, and originally endowed with "on site" science labs for field research. That stuff would have been torn out with the refitting and space would be given over for pure storage of men and material that would require transport from orbit to a presumably contested battlescape. So, much less space given to fuel tanks and more to, well... tanks.
The craft would presumably be named in association with the star or constellation for which the Zodiac-class ship they serve was named.
BTW, beautiful work, V. It goes w/o saying, but you are the best.