We stayed in Milini, in between Cavtat and Dubrovnik. A small village with a couple of bars and several restaurants and only a sort bus ride to Dubrovnik (or boat if you fancy it). Absolutely loved the place, you won’t be disappointed.
+1 for Mlini/Srebreno, we stayed at Srebeno end of this little area in the Sheraton. Perfect spot and as you say can get into Dubrovnik and Cavtat on bus or taxi boat for a change of pace/scenery. Very short transfer as well from airport. 100% will be back