A friend of mine is vegan (the family with her), and her dd is allergic to nuts. When I stayed with them last summer, there were many meals that didn't have soy in them.
There are many grains you can find that are alternatives to wheat:
oat, bulgher, amaranth, rye, rice, barley, and so on. There are flours you can substitute for wheat flour in just about everything from bread to fancy french pastries. Think about it. 12 grain bread has eleven grains besides wheat. Most organic food stores have plenty of alternatives for those who can't or don't eat wheat.
The same is true of soy and nuts. I personally don't like most nuts in most things, can't think of the last time I had any. they're really not hard to avoid. As for soy, there are plenty of ways to get your protein that don't involve the oh-so popular soy:
think beans (dozens of kinds), a variety of grains, etc.
And there are plenty of products that do the dairy substitute thing without soy or wheat gluten (you might just have to get over the lack of meat subs): Rice milk, rice milk-based frozen desserts (like Rice dream) come to mind, for example. Cheese substitutes might be trickier, but for most things those can probably be done without.
There are many, many foods that don't feature nut or soy or wheat. Pore through those cookbooks, read labels, be creative, and you shouldn't have to worry about variety in your daughter's diet at the expense of her health.
breastfeeding, babywearing, homeschooling Heathen parent to my little Wanderer, 7 1/2 , and baby Elf-stone, 3/11!