If you are looking for a good liquer with a good hechsher i would rerccomend either shmerling chocolate, or there is a liquer called advoscotch, which althoughg whiskey based is only about 17%, and is an improvement on advoca’at.
as an aside, brittish researchers have shown that people who drink 40 ml of liquer twice a week, or 200 ml of wine are healthier.