FYI, this is basically what I do as well. I am most often done lifting between 7 and 9 at night. I have a 4 scoop serving of Surge between the last 30 minutes of my session and 30 minutes after the conclusion. About two hours after that I have a big salad with oil and vinegar and a 6 oz bag of precooked chicken. IF I wake up in the middle of the night, I'll have a big spoonful of peanutbutter, some almonds or walnuts, some Hood lowcarb dairy beverage, or a scoop of Low-Carb Grow! and some fish oil. I've done this before ... it works.
To answer your question and reinforce what someone else stated, slow digesting protein and a little fat (for health and to slow digestion even further) are recommended. For me, it's almost always P&F or P&C. The only P only meals I have are just prior to trainig if I haven't eaten in about 3 hours or, as mentioned in the Fasted Cardio Roundtable, prior to a cardio only session.
Ideally, we should target our fat intake towards the end of the day. Working out as we do at night throws a monkey wrench into this. FYI, here's how my meals breakdown:
(1) upon waking P&C (nonfat milk, oats)
(2) lunch #1 ~ 10-11AM P&C (oats)
(3) lunch #2 ~ 2-3PM P&F (fish oil)
(*) sometimes prior to lifting P only
(4) PWO 4 scoops Surge
(5) dinner as mentioned above
(*) middle of night snack as mentioned above
That's 5-7 feedings per day totalling of 3000-4000 calories per day. My P source is almost exclusively Low-Carb Grow! My nutrition is so simple it is scary. Dan John has a note in his diet and nutrition article to list all of the foods you eat during a typical week and suggests that is less than 20. Mine is less than 10:
peanut butter (go with nuts?)
Again, I hope this helps,