That's a pretty cool set up. I still think 6 is too many though. You have a lot of vertical space it looks like, and if you veg just one week the plants won't take up all that room. I'm thinking like less than 2 feet for a sativa and less than 3 for an indica. Of course you said train, and with the right training you can mostly make a plant go where you want. I would probably consider putting a Daylight or Sunlight fluoro strip down each side, since by the time the plant reaches the top, the lower growth won't be getting light. I wish you the best of luck, and please keep us informed.