The last area that I would cheap out on is hydration, I'm in South Carolina so we get some heat and humidity out here.

I use a Camelback Mule which holds 3 liters and has plenty of room for clif bars and other random junk. It was $80: http://www.amazon.com/Camelbak-M-U-L.../dp/B00437TWK0
I did a 4.5hr ride in the heat this weekend and still had ice in the bag when I got home.

One of the benefits of the Camelbak is that you can replace the bladder / hose / mouthpiece and the bag itself is very high quality so it should last for years and years.