Yes, tapioca and potato starches are both grain free, as is wild rice. Although, I try to use all three somewhat sparingly.
I'm not sure what you can use to sub for the almond flour, maybe others will have some ideas too. I haven't tried this myself but I've read that you can make your own seed meals using pumpkin or sunflower seeds and substitute those with any nut flour (except coconut). I can't do almonds, although I can have other nuts so I have been subbing half hazelnut and half chestnut for the almond flour. I know that doesn't help if your son can't have any tree nuts though. There are plenty of recipes using coconut flour alone, I highly recommend Spunky Coconut's Grain Free Baked Goods, that is my favorite cookbook by far. You'd definately find muffins/cookies there. She uses almond flour occassionally, but not always, and if so it's often in combination with coconut and perhaps tapioca so I'm sure the homeade seed meals would sub just fine.
I haven't found any good wrap recipes that meet our criteria, so please share if you find anything.
Also I have to point out that giving the kids a homeade grain free treat can definately be done without the processed white sugar, and I also love to bake! You should look into using small amounts of raw honey or coconut palm sugar. Sometimes in combination with xylitol and or stevia which are zero sugar, you don't need much. I agree that the kids deserve the healthiest NO sugar alternative and with a little creativity they won't feel deprived at all. Once you/they get used to it, you'll never want to go back. Eating healthy just feels good, especially when you enjoy being in the kitchen which it sounds like you do.
Congratulations on your daughter's success so far, keep up the good work!