Justin: Lets put it this way. Today, you have limitations, that may or may not be present in the future. Keep an open mind. If you have room for a 4x8, you have room to build a 1' to 18" x 8 module, one leg of your donut plan. When that's done, expand. Your wife is concerned about finances now. You just got a better job, that pays more, In time, that will bear fruit. Your world and outlook will look different. When she sees the concept of using modules is not a space eater, she will change her mind about what you are doing.
I stubbornly stuck with the Island (table) layout for entirely too long. It occupied 5' x 12' not counting extensions, and I still was unhappy, because the trains were still chasing their tail ends. Finally, I stopped beating my head into the wall, and demolished the whole thing. I started with 2'x 12' against the wall. It's now up to 45' in length, around the wall, no wider than 28" in depth.
The track plan is what I want, and it works. I have one crossover to reverse, and some wiring to finish, but I'm almost ready for basic scenery. I still have roughly 20' to build, without encroaching the center of the basement. I also have plenty of room under the railroad for book shelves and storage. The rest of the room is open. When done, I'll have a full scale mile to run over (62'), runarounds, sidings and plenty to do. I started this build during the summer of 2016, and I'm not there yet.
Moral of stories. I lived through a lot of what you describe about yourself and situation. I learned the art of compromise and patience, and have for the first time, a workable layout that resembles the railroads I lived near as I was growing up. I managed to compress four miles or prototype, into one scale mile of model railroad. Not sure how the last leg will work out yet, but it will be OK. Oh yeah, wife now actually likes the railroad, and doesn't complain about my purchases, as much.
