Any way to modify a stacks docker-compose after creation?

I see that I can make some small changes like scale and service links after my stack is created. But is there a way to make actual docker-compose or rancher-compose file changes other than deleting the stack and recreating it?

No way to do that through the gui? I see I can upgrade each individual container. but I have my entire stack added through the GUI by supplying a docker-compose and a rancher-compose.

No, there is no method in the UI to be able to upgrade a stack through the UI. Please feel free to create a github enhancement request.