I reckon its best to share what type of genetics you are using, then more specific answers can follow.
from the little i know, all strains grow differently, with some having thick/thin branches, quick/slow recovery times, response to training and topping differently etc.
Your yield will be controlled by these factors just as much as your feeding regime and care etc.
Also, are you planning on growing in soil, or hydro or coco etc
Just trying to help, hopefully the real growers will be along shortly.
Good luck m8.
Thats a small tent, you should use plants/clones/strains proven to be small growing. I would struggle to get everything into a box this small ( light, ventilation, filter ). Also 12:12 from seed should be worth a look. If the plant(s) seem to be getting tall grow just one or two and scrog them.