first time "professional" grow! Need opinions and help!! thanks

Hi everyone, i am new at this forum and this will be my first "professional" grow with a good enviorment and i need some opinions to help me out please

My setup:

1 HomeBox XXL = 2.40m X 1.20m X 2m(height) - 2.88 square meter
2 600W HPS phillips son t plus green power with cool tube
Extractor RVK 150 A1 400m/3h.
Intractor RVK 125 A1 300m/3h.
Odor control - carbon filter and vaportronic.
Climate control to control air in and air out, also controles temp.
hensi nutrients
strain - I didnt choose the strain yet

1 - how many plants should i plant, i was thinking 36...in 26x26x26 pots of 16 liters, since the optimal lumens per square meter is 7K if I am not mistaken this will have more than enough light...

2 - can anyone please tell me the best lights for seedlings? in terms of growing them fast and make them healthy!

3 - i was thinking about co2, but i know nothing about it..still should give it a try? if yes what equipment i need to buy?

4 - strain, what is a nice potent really good strain that gives a nice yeld?
my goal is to get 50g-70g per plant which i think is possible with the right temperature and humidity at all times...with the right dosage of nutrients and right amount of watering...but correct me if I am wrong.

ALL THE OPINIONS WILL BE GLADLY APPRECIATED!!! THANKS IN ADVANCE

Thanks
resetme