Heroic is good, cloud saves are on Beta at the moment, on some (a lot) GOG games cloud saves aren’t present. On the other hand some games do have the option. Heroic does allow you to configure a runner per game basis which is helpful in some situations.
If you do play the game on Heroic and it doesnt have cloud save, when/if you copy paste all the files or import it (copy/paste) to something that can run their client like Lutris/Bottles with galaxy all the achievements and saves are transferred and can be saved in the cloud. You do have to run the game at least once after transferring all those files to the client.