SEEKING LIGHT/VENTILATION ADVICE - NEW GROW ROOM - GRAPHICS INCLUDED

Thanks for taking your time to read this!
I am a second time grower and wanting to take my cultivation skills to the next level!

I have an open closet that I've decided I will turn to a grow room! Dimensions are 5'x2'x7'
The graphics I have included are to exact scale of room and pots.

My main concern is lighting, with such limited head room. After pots I have a clearance of 2'10". I would like to venture into HPS/MH usage but am unsure with such space. More input on what lighting would best fit my situation here is greatly appreciated! (Side note: with such limited head room SCROG has been widely recommended, would me training smaller plants allow for HPS/MH lighting in my tight squeeze?)

Second concern is ventilation. I am not worried about the smell so much as I am concerned about lack of proper o2/co2 exchange. There is a window/window well in this closet but I would like to avoid any exterior penetration. How would you approach this?

Please let me know if I am headed in the right direction, what I can improve on, and options that I have.
Thanks again!
-Padfoot

To help I need to understand the natural temps we are working with. Is your home always cooled to a certain temp? What is the temperature inside your home? Is it possible we can run the light at night and pull in fairly cold air directly from outside through the light hood to help combat heat from the lamp? Can you possibly afford to run a water chiller + icebox style cooling system? (Water Chiller + Icebox you can google it).. What about the room next to the grow can we exchange air with that area?

My friend lives near a year round stream he uses a car radiator submersed into the stream he pumps water through it and through his icebox inline cooler. He's growing right now while I'm down for summer. Those who are creative go getters will usually come back with the prizes

Temp. and RH are not too much of concern. the room this closet is connected to is temp. and RH controlled for another project! Also well vented for co2/o2 exchange. Temp stays a constant 70 and around 50 RH. Plenty of fresh air coming in, but I am unsure where / how to exhaust if out of the closet. Again best case scenario not penetrating wall/window in pic 4.

I want to keep it as basic as possible and I believe I can do that with my current 'climate', though I do not know of the best light/wattage. I am willing to invest in quality lighting. ( my last grow was CFL, eh )