Still, essentially you want to compare subspecies. I still think that it is unlikely that anyone can identify having any specific species with 100% accuracy.
When it comes to difference in temperament - I do believe this lies more on an individual basis than it would with any subspecies. I know a few people who have siblings of Zuri. Actually, if I remember right, Itsy might very well be Zuri's sister. And both birds have differences in temperament (I have had both at once with me on a few occasions for a few weeks at a time and have known Itsy for a few years now).
It's one thing to have a fun thread and guess and talk generally about a bird, without linking the information to the "subspecies". But I don't believe you'll be able to get the information you really want out of it and definitively won't be able to link key differences to subspecies. You will see differences between birds, but these differences, I am confident, will lie in their individuality. The "basic" Meyer's traits, they'll most likely all have.