yup, ice certainly helps with making the smoke seem cool. Haven't tried thisout, but I had using warm water instead of cold will make the flav stand out more.
Putting different liquids in the base will actually enhance the taste a lil. Example: AF grape with grape juice in the bottom. The grape will be a lil more known
BTW you can use soda, but make sure you only put A LITTLE and then the rest of it is water. Too much soda will make your hookah have too much gassy air from the soda and it isn't fun breathing it in when you smoke