Kull,
From my point of view, the longer the team takes in getting AI faction play balance right, the better.
I never finished a campaign in EB1 due to frustration with AI factions like Seleukia and Ptolemies becoming uber-powerful with stacks of elite units while I was trying to play a slow, role-playing campaign on Medium. My EB1 experience is one of playing the first 50 years of a campaign with all the various factions, then starting again - the game only remained 'historically balanced' (but still interesting and challenging) for me in the early years.
So please take your time and beta-test to the max with long test campaigns! After 6 years of waiting, what's 6 months more?
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