Great sounding recipe Belle! is right! Like you suggested it does need some celery. In moderation though. Just enough to barley taste it! That’s the secret to using Celery in recipes. Done right most folks would not even know it’s in there. Kinda like on a Chicago Style Hot Dog.
But… some big chunks, pinkie nail size, might be good in this ??? Hey, it’s a brisket veggie soup.