Kel -
with the snafu's I had with the RBG for GZ's cycle 3 terms, I ended up having to manually distribute the era's to make sure there was an even distribution. In the end, I ended up having each match include one Early, one Mid and then one either Late or Advanced era game. (the order the matches were played was more or less random)
I would propose you do something similar for the next cycle in here (should everybody agree).
I personally like it as I think it both tests fleets across the spectrum of eras, as well as avoids races automatically getting hosed if they are weaker in a certain era.
Anyway - food for thought