To your first point, the droids in question do seem to follow the “easy designations” as you put it. In fact, they are often referred to in the film by them. Examples: Luke often refers to R2-D2 as just R2. And C-3PO as 3PO.
I still don’t buy into the notion that these were unique “names” at all and not “model numbers” though, but thanks for the discussion.
TIL: there is a version of AdBlock out there that assists with bathroom trips… More information requested, please and thank you.