Well you know there isn't a supplement law that says you have to take an entire recommended serving

. But seriously I used to ingest that much growing up just in eggs or fried chicken.
BCAA's are essential amino acids. Which means your body cannot produce them. But you will get PLENTY from the whey and from all the other common protein foods you eat. Creatine you could take but I agree for now just stick with the whey.
You can use the why for pre-workout. X-tend wouldn't hurt you but you could just use whey the whey for preworkout.