Lookin' healthy! If that's going to be your long-term box, one thing you could do is to flower two plants in there, by moving one to a closet or other dark area while the other is in the light, then switch places with the plants each 12 hours. A poor man's light mover, and a bit of a pain, but that would potentially double your yield. Plus you could have two strains going at once that way, with only the one flower box.