[Edi]

#3 goes pretty much against the idea of communions, which is to provide a temporary boost to the master for the duration of a battle. Would be the same as a mage with E2 casting Summon Earthpower and then forging an E3 item without actual path boosters.

One turn is one month, and the item crafting process is complicated, involved and spread out over the month, which is way longer than a temporary communion could be maintained.

In my opinion, such permanent communions as the idea entails run counter to the way of how magic is supposed to work in the Dominions universe. Your mileage may vary.