If you have a breathing problem dont use a stop or fast fix.
Tap water tempered close to the dev temperature is ok instead of stop for film. You only need stop for paper.
Plain hypo will extend your wash times for the same permenance, and is a lot easier on the throat & nose, it is cheaper.
If you move a lot of air you will get more dust. If you live somewhere hot you may need ventilation.
For the last 13 months I've only used a Kiev (or Contax), apart from folders, Fed's, Zorki's, M2, etc.,... and a digital to record dismantle sequences...