If you use a 250w your space should only be 2.5'x2.5' max. If you use 400w (which i recommend) you can do 3'x 3' . The "scrog" net should be the same demensions as your room. So 3x3 if your using 400w. The strain you use is up to you. But honestly i dont like your choices. Order a 5 pack of any tga strain. They dont come femenized but youll most likely get 3 females from a pack of 5.
Heres some strains.
1. Ace of spades
2.vortex
3.agent orange
4.querkle
5.jack the ripper
Those are just a few. Look at all his strains. He tells you the best way to grow it whether its sog, scrog, top, untopped etc.
As for medium and nutes, i highly recommend keeping it simple. Just get a bag of general hydroponics maxibloom and some dynagro protekt. Maybe some calmag from GH. Make some hempy buckets (very simple to do. Just search) and get some perlite as the,medium.
Use 7g of maxibloom per gallon of water.
If you do a little research on what ive said youll get a good idea of what to do. Its simple and you should get good results if you do it right.