Numbers apparently work better for non-native English speakers and non-English speakers. I am going to slightly miss the "A as in Airplane", "B as in Blue", "C as in Captain", "D as in Destination", "E as in Engine" groups though.

If you look at the groups side by side, EvenMore seats move up one group to join M1/M2 and the early boarding perk (and maybe Blue Extra, it's always been really unclear) moves up one normal group (ahead of courtesy boarding). I think it makes sense to improve the perk because when I was doing 25for25, I frequently got group B before I picked the early boarding perk.