I usually just throw whatever vegetables and grains (wild rice or barley) I have into a pot and add some herbs and spices. I like hotter spices, so adding crushed chili peppers and that sort of thing makes up for the lack of salty flavour. Also, garlic powder can be a good substitute for salt in recipes where you don't want it to be bland. It's definitely a different taste than having salt, but it definitely gives the soup an actual taste instead of just tasting like water. I also replace salt with garlic powder in bread recipes. Make sure it's actual garlic powder though, not garlic salt.....or that just defeated the purpose. lol.