Re: too much ice?
If you use milk in the bottle make sure you clean out everything super well. Even then, I had some bubble up into the chamber of a cheap Chinese hookah and essentially ruined it. Not worth it.
Ice is a godsend in small amounts. A handful will do ya. We sometimes use more if we're going to be smoking outside (the heat around here melts it in minutes.) but too much ice will kill your sessions. On the other hand, a little bit of ice can do wonders for smoothing out some of the harsher flavors.