I think that my personal experience was as good as it gets, but experience sometimes is different from theory. The OP lineup is probably fine, and quite scientific, but since my love of firearms has stood the test of time, I will relate it. Whatever my experience was, it worked.
I had over a decade in .22 rifles by the time I was 16, and had shot many thousands of rounds by then. The I got a few centerfires, but kept disappointing myself by my inadequacy in rifle marksmanship. Then I got a 9mm Walther P38. Somehow my lack of ability with rifles was forgotten when I discovered that I had an aptitude with pistols. I had over a dozen rifles and autopistols before I bought my first revolver. Hated the recoil, so I got into reloading, then historical collecting, primarily lever carbines and matching revolvers, plus a few black rifles. Started CCW in my mid 20s, quickly settling on the .380 Walther for my carry piece. I always carry the same gun - only changed up once, to another .380, this time a Beretta. I've got my reasons, and they are mine. Your mileage may differ.
Insofar as a beginner arsenal, it seems to me that some .22s for cheap, virtually unlimited practice is a good place to start, but so long as you own an autopistol, a centerfire rifle and a home defense shotgun you are well armed - a heavy caliber revolver becomes important if you spend any time in the woods also. Then you need to double down, so that in case you need to leave a gun at the smith you are still adequately armed.
I do not believe that there is a blueprint for proper armament - you need to be comfortable with whatever it is you have. It has been so long since I thought that I needed to buy something to be properly armed that I can not speak to that, but the thing is that these things are so personal - there is no such thing as right or wrong in this. The only one you need to please is yourself.
BTW, I would never buy a Glock or a Chevy, but that's just me. Tried 'em, hated 'em, 'nuff said.
