Water Spots vs Other?

I couldn't say; it's been a while since I processed any Vision3. I can't remember if my freshly processed film perhaps looked the same back then. And I never tried it with blix. Generally speaking, I wouldn't expect a marginal overdilution to be a problem.

Just an update. I got in touch with Kodak and they kindly suggested rewashing, which seemed to have fixed / greatly diminished these halo marks. The question remains what caused them in the first place. I'm still awaiting word from their processing department. Please see pictures below.

As an aside, after I re-washed the film, I noticed brown spots that weren't there before. On the negatives, these correspond to light coloured spots. Any ideas?

I had exactly the same problem you had. It was stain from final rinse chemical when i dry in the cabinet.
I just put my films now into processor and dry. no problem at all.