I typically make a big pot of soup every week, and have a soup + biscuit (or other bread) lunch most days. I previously posted about adding beans, cabbage, and mushrooms to make French onion soup into something more filling. Yesterday I incorporated beans into cream of tomato soup, which worked pretty well. Proportions were about a half cup of dry small white beans per quart of soup being made. I soaked and purposely overcooked the beans, then added the rest of the ingredients to the beans and their cooking water. Once everything has simmered and been pureed, I don't think you'd know it contained beans. Had I thought of it, I'd have included a little wine or vodka, since alcohol has the ability to release some of the tomato's flavor compounds. I was using canned tomatoes and that might have given them some extra zip.
I have read about pulverizing oatmeal and using it instead of dairy for "cream of" soups that traditionally go more heavy on dairy than cream of tomato does. I tried oatmeal in soup once and found it too mucilaginous. So I think beans (or cauliflower) would be a better way to reduce or eliminate dairy in other cream soups.