If we're going down the cocktail route, just order yourself some frozen idaho huckleberries, make a huck syrup with a little sugar and water over heat, and mix bourbon and huck syrup, with a dash of bitters. start with manhattan proportions, but I prefer a little less than a full oz of huck juice.
And if you don't like it, use the rest of the syrup/compote as a glaze or sauce on your fish of choice, starting with salmon and a little rosemary.
On the G&T front, the secret ingredient is to bruise a couple of juniper berries and throw them in the glass...