Slightly off topic, but our favourite nightcap is Glayva - a whisky liqueur from a blend of whiskies. Taken over ice.
Late FIL worked for White Horse, later Diagio and when he passed away, we found over 100 various bottles (from basic Red Label and other spirits, to limited edition collectables. ) Due to customs, we couldn't bring much back with us, so split most between his family still living in Scotland.
As for any suggestion to add Coke!......what a waste. Either neat, over ice, with a splash of water, or providing it's not an expensive bottle, then maybe with something like Canada Dry. Does taste good with Irn Bru........!