The size of the workload is manageable because he enjoys the hobby, and intends to plug away at it for years. Even so, he'll need a way to make the repetitive parts efficiently. Staterooms alone number in the hundreds.
My biggest concern is how he can devote so much floor space to the finished model, and for how long in the years after it is finished. At scale, the saucer will be 17 feet wide. From bow to hangar doors, the overall model (with no warp engines) will be 28 feet long. That's 476 square feet of indoor space, not counting the needed margins for a person to be in the room with it.
The length reminds me of another large model, the 28-foot Titanic miniature built by 20th Century Fox for its 1953 film of the same name. You hate to throw it away after the movie is made, but finding a place to put it is an issue. From 1972 to 1985, it was displayed at Northtown Mall in Blaine, Minnesota. Now it's at a museum in Fall River, Massachusetts. It was lucky to find a home— and its width is substantially less than the Enterprise model we're discussing.