Just an idea- the wife and I are craft cocktail enthusiasts.  Some of those fit pretty well into low carb, especially if you go back to ones that originate before the Prohibition era.  (Lots of sugar got dumped into sub-standard booze to make it tolerable in the 1920s-30s.)  But anyway- playing in that world has really opened me up to enjoying different bitters.  Standard Agnostura bitters with bourbon and water is a good starting point if you like a minimal sippy drink.  Expanding into Fee Brothers, Bitter Truth, or others who have made this into an art form recently might be worth a try if you want to have a decent whiskey with just a touch of flavor.