Good start.
I have a 40 gallon I'm planting now too, so this thread will help me out.
If I were you, I'd remove the background and paint it black...it'll bring our plants out more.
Your 70MH lighting is good, but the plants on the sides might suffer and grow towards the middle instead of straight up...how high is the light mounted off the tank? I'm in the process of geting materials to have a 2x70W MH setup instead of just one for a better spread.