I took an opposite track. As a new straight shaver I preferred the large "meat choppers" because they seemed to compensate for lack of skill and get more whiskers. As I gained experience I began to prefer the smaller ones. My favorite size is 5/8 because for me there's nothing finer than one of those fine tuned. 9/16 and 11/16 are only 1/16" apart so I really don't notice much of a difference. I have one 4/8. It is a nice razor but I haven't used it in so long that I forgot what it was like. But that's still only 1/8" difference from a 5/8.
In Shaving Made Easy (
https://archive.org/details/shavingmadeeasyw0020th), they suggest that 4/8 is the best on pp.15-17.