I'm not going to say you're over-thinking things, thinking and being logically analytical is good.
All three are very good products, can say anything bad about them. I've used all three, but I never combined them with 601, never had such on hand to try.
One thing you could try, and there would certainly be no harm-foul, is try #111 first. (if you want to toss a few drops of 601 on a applicator pad too on a whim, go right ahead)
And sample the results on one panel. If you like the results, carry on, make yourself a adequate mix of 111-601 and go at it.
As I see it, just about every protectant product under the sun has some sort of carrier solvents in the formulation. Even with pure Sealants, Carnaubas, and Hybrids, there's going to be some degree of cleansing action occurring, cutting through some of the cruds that might be on the paint. Dirts, maybe not so much, but greasy smearing, oils, and maybe pollens-fallouts might vanish off the paint.
As for the differences in longevity-durability of 501-105-111, I think it comes down to cutting hairs as to the time differences as to how long each might last. Might it be a week? Or two?
If that's a highly important aspect and goal that you're trying to achieve, a long protective life without returning to a full blown detail then I might look to Collinite #476 as a more conventional product. Or as some others like, PNS.
I'd like adding....Not sure what, if any of these products you already have on hand? If some, or all, then experiment some.
No doubt about 501, it cleans very nicely. Not many other products that are sort of an AIO compare. And no, this isn't perhaps the equal of Blackfire AIO.