Yea they look ok.
Maybe one for extraction and one for intake OR two for extraction, one on each side of the room at the top and use passive intake holes at the bottom?
You could link up the output side of the two fans via duct into one side of a two way duct splitter then the other single side of the splitter going into a carbon filter to scrub your air?
Dont have too many bends in your light baffling pvc pipe, every bend restricts airflow, so keep any turns or bends to minimum.