It is customary in Italy, Serbia, Slovenia, Croatia, Sardinia to make infusions of various flavorful fruits or savory herbs. Typically these are called "Grappas" with the flavor being mentioned. Limoncello is one variant with lemon zest used with either grain alcohol, vodka or grappa as the alcohol product. Many places offer an infusion of billberries ( they look like blueberries to me), grappa, sugar and water to make Mirtillo (Mirtu in Sardinia). There are so many different variations of these infused liquors and they are all good. I have an Italian recipe book with about 100 different recipes.
I once stopped at a roadside stand in Croatia. I swear there were more than 50 different flavors of grappas on the shelves, fruits, citrus, and savory herbs. So, use the ingredients you want and the end result will be good. If you want it to be great, then wait at least a month for all the flavors to infuse and the taste to gentle out.
My latest batch of Lemon Shrub is about 10 months old. I think I'll go looking for the bottle and see if the taste is still good.