1. Use AA for IGF. You are correct. AA will make it most stable.
2. Yes you can combine cjc, ghrp and igf in the same pin, as long as you are planning to use them at that time.
3. Bac water will have no sting. AA will have a little bite, but it isn't a big deal. I fill a 1mg IGF vial with 2cc AA, so that the volume of liquid is large enough to easily measure.
4. Dosing :
IGF looks good. I have run it this way many times. Recently, I have begun increasing the dose, after several wks. I'll run 3 wks at 30mcg, then up it to 60mcg, until the 1mg vial is done. For GHRP 6 and CJC w/o DAC, I would use 200 to 300mcg GHRP with 100mcg CJC, 2-3 times a day. First thing in the AM, at training with IGF and then at bed time. I would run these peptides for several months at a time. I can't personally say if they are less effective over time. I usually add them to my HGH program for periods of time that I'm training harder, like during a mass gaining phase or contest diet