in my opinion you are comparing apples with pears here tho.Nah. If the set is 100% better for someone playing on God-mode with
all magic buildings and
all level 30 wonders and
unlimited culture and
unlimited PoP spells
unlimited MM spells
logs in every 3 hours 265 days a year
then I'm very comfortable saying that for a normal player the set is absolutely amazing.
For a non-theoretical real example, my Beta city has
increased T1 production from 72,648 to 99,848 a 37% increase
increased t2 production from 70,694 to 103,494 a 46% increase
increased t3 production from 60,864 to 163,164 a 168% increase
That's real, not theory.
and I also expect to get 2 trees to increase my mana from 85K to 200K
might get lucky and grap 2 of the other ones as well, add 4 KP per day to list of goodies.
As for upgrading, not a concern. Either you are a god-mode player and have dozens of RR spells coming, or you play normally and the set is better in chapter 5 than factories are in chapter 13. (per square) or somewhere in-between where it's still amazing for 4-5 chapters.
A player with all magis buildings all wonders etc, is playing for rank usually. They dont want a set that gives them loads of goods but no points
A player who wants to play efficiently, those will want the set badly, but they usually arent that interested that much in ranking.