Low Sugar Acidic Drinks?

So I'm kind of a genetic oddity with the various conditions I've got going on. I have vasomotor rhinitis that causes a nasty postnasal drip all day, every day. I occasionally take mucus relief for it but that dries me up, so nothing is more refreshing than a nice cold can of Coca-Cola or lemonade for me. The lower the pH, the better, and fortunately I've been told by my dentist that I have abnormally corrosion resistant teeth, and told by my doctor that my water intake (80+ fl oz / day) dilutes the few low ph drinks I have a day.

The problem is the sugar content. Naturally, drinking a can or more a day is a lot of sugar to ingest. I've tried diet drinks and I've tried plain soda-water, but that runs into another issue: I'm one of an unfortunate statistic of "supertasters" (stupid name), which means I'm HYPER sensitive to bitter compounds. And all non-sugar sweeteners, as well as unflavored carbonated water, are bitter as hell for me. Seriously trying to drink diet sodas tastes so bad that I can't even tell it's supposed to be sweet, and unflavored sparkling water somehow doesn't taste neutral, doesn't even taste sour, it just tastes like when you accidentally get medicine on your tongue to me.

So I'm trying to branch out from just drinking Coca-Cola, but I don't know what's out there. Are there any drinks out there that: A) are acidic (from carbonation or otherwise, bonus points for citric acid) B) contain less sugar than Coke 39g/12floz C) DON'T use sweeteners other than cane sugar or corn syrup D) aren't bitter or dry tasting?

It just seems like everywhere I look for alternatives, manufacturers try and push zero sugar drinks, either containing no sweetener or aspartame/stevia/sucralose/etc, rather than trying to make products taste good with like, 15-25g of sugar per 12floz can.

Is what I'm looking for out there, or is it just impossible? I'm open to honest answers and discussion.