You now have to run all those programs in the same namespace, on the same machine. There is no possibility to run some of the programs somewhere else (without building a new image).
No, pod is a collection of multiple images, not a single fat one.
Sorry, you have to rebuild the top level representation, which I guess is now called a Pod.
No, Pod is designed for multi-containers grouped to run on the same host, primarily for sidekick process, like syslog.
If you want to multi-host deployment, it is similar to CloudFormation. You can still use multiple pods to compose a distributed app.