Nintendo hasn't released new games to NES or SNES Online (the two services that allow, upon payment to the Switch Online service, access to a rich catalogue of retro games for NES and SNE) for a while.
Starting on May 20, however, subscribers of the service will be able to play Operation Logic Bomb, Panel de Pon and Wild Guns for Super Nintendo as well as Rygar for NES. These are all very important games that are worth rediscovering in case you missed them at the time.
You still have a couple of weeks to take advantage of the free trial week of the Nintendo Switch Online service, which Nintendo recently reinstated following the fact that many players are forced to stay home because of the Coronavirus.