Thanks so much for your detailed feedback! It's really complimentary!
So re your calamity/pecking order rules questions - I think what you missed is in the pecking order rules at the top of the board. Whenever an enemy player removes a clutch, the top pecking order card is discarded. This means that you can end up with fewer than 6 visionaries in the pecking order, and can trigger calamity with fewer than 19 warriors on the board. If you suddenly have fewer visionaries in the deck than actions you can perform, you'll trigger calamity when you try to resolve them on your turn.
This also allows other players to manipulate your pecking order, and forces the flock player to think carefully about their order - if they put their most essential action on top of the deck, to guarantee they'll have access to it next turn, other players can destroy a clutch to discard it, putting that visionary out of action for the round. Alternatively, the flock player can bury the actions they want several cards down the order, but risk not being able to use them if too many of their warriors get removed. I think it's both an interesting layer of tension and allows enemy players to have some say in when calamity occurs - do they risk destroying a bunch of clutches knowing that that will make it calamity more likely next turn?
As for where the visionary cards are - At the end of our turn you set your pecking order and all 6 end up on the slot on your board in order. Then, if during opponent's turns any are discarded, they are moved off the stack and off your faction board - they cannot be resolved in your next birdsong. In birdsong, you resolve the remaining cards in order from the top down. If you're ever asked to resolve a visionary by the coop track and no visionaries remain to be resolved, you trigger calamity.
I hope this helped clarify your questions! I'm sure there are clearer ways I could have worded some of these interactions. Do you have any suggestions?
Thanks again for your feedback! Glad you find the coop track effective (though I should clarify somewhere that the coop track here takes the place of the supply for warriors)! The idea of an automated farmer stomping around the board is really fun!