I agree with John! Go with all loops 054, then you can run the same cars and engines everywhere. One more thing to think about is spacing for overhang on curves. The only way I know to be sure is setup some track like you drew it and make sure nothing hits as you pass even just pushing cars with your hands. Sometimes the middle of a car will be a problem too.
Regarding the door, I put a pocket door in mine and it’s worked well. The only thing I saw in your original design was adding a second line so you would have a dual run. That’s been done. You may want to elevate the outer loop (in the back)for viewing and interest if space allows.
Have fun. It’s your world.
Would it be beneficial to have a lift out/lift up section lined up with the closet? If you put the lift out lined up with the closet, having the lift out removed might give you more work space in your work closet... or did I misunderstand? If you intend to work in there (the closet) having extra chair space might be needed.
I might consider putting your yard ops along the top wall, as it is the widest (left to right), and could be as much as much as 24 or 30" deep. I might make the lift out section the narrowest and the top section the deepest. I would make the center area, in other words, as small as comfort allows, while still allowing you to reach the furthest track.
I have it drawn as 3' x 6' -- if there are going to be two people inside, that would be the minimum for two fat old guys. (Me x 2) If someone else wants to watch from outside, then you might be able to make it smaller in the middle.
How important is scenery to you? In tight spaces you can have lots of track everywhere and no room for industry or structure or even an empty field.
Good luck. It's your railroad and your home.