I don't think you need a recipe with boring ingredients for soup. The ordinary stuff can be low calorie, low fat, low carb, or whatever you're going for, AND not taste like crap.

I buy stock - you can find low salt/fat varieties.
The usual veggies: carrots, celery and onions
Lean meat, or soy product or beans...or not
You can chuck some rice in - wild rice, which is not really rice, is particularly good in chicken soup
Mushrooms: if your trying to stay away from carbs, you can put a lot of mushrooms in. Virtually no calories, and lots of chew factor.
Add other veggies you like. My theory us that 3 or 4 kernals of corn per cubic inch of soup is not gonna be a problem.
Herbs and spices to your taste.

Opinion: a lot of diets seem to try to give you a feeling of control by guiding you in torturing yourself, because denial = control in some people's minds. Those of us who don't believe that need to learn how to enjoy healthy, food in healthy portions, at specific times, MORE, not less.

Plan how to include the stuff you like once in a while