I had this exact issue 2 years back and after a ton of experimenting in my kitchen and then contracting with a food scientist, I'm in now the process of starting a company making what I'm calling "premium" tonic water. I'm calling it Q Tonic because of the real Quinine. And it's made with quinine from Peru (an extract sold by Zooscape - after a bunch of agonizing I finally accepted that they make it much better than I could) and organic Agave as the sweetener. As a result, it's significantly less sweet/more sharp than regular tonic water, has 80% percent fewer calories, and has a 85% lower Glycemic rating, and it's all natural. I describe it as having a "quick sharpness and a gently rounded sweetness" and I think it mixes great with good gins. I just finished my glass bottles this week and next week I'm getting a trial batch made at a contract packer. If anyone would like to taste it, please let me know. I'd be happy to send you a couple of bottles and I'd love to hear what you guys think. My email is: Jordan@qtonicwater.com (jordan@qtonicwater.com), just drop me an email. -Jordan