It's a simple of layer around AWS so it doesn't add extra craziness some other approaches do.
As for the OP, her approach is spot on!
Containerizing your app is the first step in future proofing it. Doing so correctly will remove layers and therefore simplify things.
You now are looking at a package that can run on a laptop and run on a server with traditional techniques (upstart, systemd, etc).
You may take this to the next step and enter the orchestration world. Or not! Patience is a virtue, wait 6 more months and all the orchestration tools will be that much better.
It's all about simplifying. Adopt Dockerfile and shed Homebrew and Chef. Run containers on a "dumb" box with systemd and shed Packer.
Run containers on ECS and shed custom AMIs and userdata and nagios and...