It is over doing it but if thats what you have. You will have sick coverage! I would put
panda film on walls inexpensive n no mylar burn. If you had the money though you could go T5 for short plants or dual 400w or 250w HID. The tube is probably your best bet for coverage in this app and its small so will fit well.
Heat is always an issue. I'm amazed that those grow cabinets can even stay cool enough. If you can keep the room w/ the closet in it cool, then vent air from cool room.
Here are a couple ideas, you duct fan through filter/through light/ out of closet. If your put a vent or a peice of duct (helps if light is issue) running through closet door, the pressure will draw cool air in from room.
You might need a filter on either side of duct fun if smell is too stronge. It depends on size and quality of filter.
Or duct fan in closed loop, meaning it both draws air and deposits air outside of closet. This is best for smell but you will then need to another fan to bring cool air in.
When doing this you will want a duct for intake and exhaust on the closet door.
If you don't want to cut up the apartment door, get a peice of foam board and Velcro. You'll actually get a better seal.
Just remember the basics: Circulation and Convection
Meaning air flow and heat rises, these are main factors with cooling.
As far as too much light, I believe that is only a problem when introducing a plant to a "extreme" increase in lumens. Like going from flourenscents to sunlight. Maybe a hot spot diffusers. I would try the Equilizer, I think the S. Spreader is designed for wings.