As I've noted in some other threads, the only choice we have is whether to upgrade to gold plate or 10K gold. But stone-wise and setting-wise, they're the same:
There was a time that the basic badge was scrolled, with no jewels:
During that time, the jeweled options were close-set and crown-set (no choice as to jewels). I'm not sure when the non-jeweled scrolled badge was first offered as the basic option, but it was discontinued in 2003. The pearls and garnets (originally rubies) were part of the design approved by the National Convention in 1910.
I have no clue if there's much of a size difference over the years.