Lets worry about the budda right now and not so much the gunz..
1g per watt is going to be a challenge, but so is that shot glass grow off that some people are doing, so to each his own. I'll post up a pic when i'm done this homework bullshit. There is a really good pc grow on here somewhere with a monster plant inside, that had some great tips and tricks you should check out.
Im worried about the amount of lights you have in that smaller area that is going to be HOT without adequate airflow. I had to fuck with my box 3 or 4 times to get everything stable (temps,light positioning airflow) Test your shit out and prepare for the unexpected, like your girls getting to big and burning on the lights, or outgrowing their growing space. Test and plan is the best advice i can give you right now.