I want to drink more water?

As far as I know water is one of the best drinks in terms of hydration, adding stuff to it will only detract from that, however some drinks are claiming to hydrate better than water, notably Powerade (I think it was Powerade) in their recent ad campaigns. If you drink a lot of water very quickly it can be lethal, see the article in my sources. Finally there is a calculator for how much water you should drink - see sources again, but it sounds like you drink quite a lot, it all depends on life style, for example if you do a lot of exercise and sweat then it would be stupid not to keep hydrated, so in summary 1) No 2) Yes and 3) It depends.