So, this is what has been working so far. I decided to go back to a favorite of mine from 20 or so years ago, rice cakes. I used to love them spread with Laughing Cow cheese or peanut butter. I've been using them for sandwiches for me and DS--and they've worked well. I even brought some in a ziplock baggie in my purse to a hamburger joint to replace the bread. Much more satisfying (to me) than wrapping it in lettuce.
Also, when I make almond flour pancakes, I make extras--and we use those as bread. DS loves one with either peanut butter and banana or nutella spread on it.
I also made a recipe I found online for biscuits (I think it was from Wheat Belly) using almond flour, flax seeds, butter/coconut oil, and whipped egg whites. They were good--but I think part of what made them good was they were fresh baked. No idea how they'd work if I made a giant batch, and then froze/defrost them as needed.
I figure we'll do this for a few months and then go back and retry some gluten-free breads and see if they taste better.