Hi!
Lots of good information and passion. :-)
Just a few comments:
Hydration packs are good as you find that you will sip often which is a good way to offset your water losses. I personally find it hard to try to gulp massive amounts of plain water during a break in a climb. Also, a hydration bladder weighs less than a bunch of Nalgene bottles.
Gatorade-Koolaid or different types of gels....you've got to try them out under the actual conditions and see what works. Some climbers have used sticks of butter and dark chocolate. Viesturs likes Koolaid. Some sports gels give a friend instestinal problems. I personally cannot stand Cytomax.
Read this entire thread, understand the medical aspects and then go experiment as your diet and your physiology are unique.
best regards,
Jim