I try to avoid artificial sweetners as much as I can.
Any of the "itols"- sorbitol, malitol, etc give me the big D even in small quantities. They also give me horrible crampy gas.. - Sorry I know TMI, but I'm just sayin'...

And I can only tolerate a bit of spenda, otherwise it makes me sick.

My body just seems to reject the artificial stuff I guess??

Oh and Stevia- Dr. Oz (yeah I like him, but I don't take anyones word as gods) say's that it may cause sterility in men. Don't know if it's true, I'm just sayin'... And I guess WE don't need to worry about that, but I dunno, I just think I'll pass.
If I need a little sweet I use agave nectar. Super sweet punch in just a small amount.
As for your water, try adding orange, lemon, or lime slices. Mint works well too.
I'm a big water drinker, so sometimes I add a slice of orange to spice things up. I also drink a ton of fresh brewed iced green tea. YUMMERS!