Looking good so far, but I share the concerns about the cardborad/fan interface. I can't see that cardboard lasting the course, man. Is there any way you could mount them to something more solid and then use ducting, maybe? At least that way it wouldn't be the fans smashing into your plants if the cardboard were to fail.
The accepted rule of thumb around here is 100 true watts (not equiv) of CFL per plant, but more light = more bud so use as much as you can get away with. Obviously, don't let the temp rise too high, about 75 deg F if you can. Mine got as high as 91 deg F last time and it seriously affects growth/yield.
You look like you have if covered though
Good luck man, and +rep for starting
