Well I would definitely go hydro. I'm not a dirt farmer. I would buy 2 of these ebb/flow tables maybe these.... Big Foot hydroponics system from 4 hydroponics.com by Growco Indoor Garden Supply
and go from there. Two 4 watt cool tubes would be fine for these dimensions, use mylar too. Definitely fresh air intake and extake in addition to venting hot air out. As for odor control, I guess a carbo scrubber would do the trick.

Man I wish I had a spare closet like you!!!!!!