You get 5 stars from me just for doing it.
I liked the article but felt there was information missing that might help future Ex Batt keepers.
Making sure you can access vet care for chickens is a sensible thing to do before you get them.
I know BHWT can assist in this.
Feed the same feed if possible while making a gradual change over to a higher protein feed .
Don't let them free range the garden as soon as they arrive. I know you've covered this and as you write, most will be reluctant to leave the safety of the coop initially. The problem is, out in the big wide world, they don't know what is andd what isn't good for them to eat. Quite a few Ex Batts end up with crop problems because of this.
Anyway, loved the article and hope the experience doesn't turn out too hearbreaking.