After the broth comes to a boil lower to medium high heat and cook for 1/2 to 3/4 hour more then add diced onion, carrots, and celery. Continue by adding all other ingredients except rice, potatoes and chicken.
Cook vegetables for 8-10 minutes and add either potatoes or rice, continue cooking until they are done. Add chicken at the very end just long enough for the chicken to get hot (it has already been cooked and will be tender and moist to eat).
Of course you can make dumplings but you may want to cut down on potato or rice amount as the dumplings tend to soak up broth and starch from potatoes or rice will also make it thick.