@ZodWallop: That won't answer your question entirely, but the main difference from v2 to v3 was the move to a natively variable font.
I don't recall massive glyph shape differences myself, but I didn't use v2 for long (and mostly not at the same weight and not on eInk devices).
I don't think I ever used v1, though, but I may be mistaken.
As usual, if you're happy with your current results, don't poke the bear
.