Lots of times I use side projects as a way to explore new stacks, deployment approaches, etc. The goal of the project is not to deliver anything, it's to learn so that when I go to do my next "real" project at work, I know what works well and what doesn't.
Where can one learn about different deployment approaches?
For a side project, pick one on that you're interested in on each side. For example, maybe try out CircleCI and deploy to Google App Engine. Then you'll learn two new things, maybe one is great but the other is a pain in the ass. You can take the one that works well to a "real" project and talk knowledgeably to the architecture.