Yes, if you use "Small" it's more logical to use "Large" in stead of "Tall".
But to be honest, the difference in size between the "Small date" and the "Medium date" is very difficult to see, certainly if you have only one of the two, so nothing to compare with. I think "Small date (with a low 6)" would make it much more comprehensible.
Yep, while I was typing. It's ok. My thought was that the 6's are distinctly different and might be a good way to distinguish them. As per Red Book closed 6, ball-top 6 and open 6. Your choice.
I'll stay with what I can see, ball-top honestly doesn't tell me anything, but then I'm not American either.... and we don't need to cater for RB users, they already have the book!