Yes, in fact that's what I do! The issue is I need to account for any new servers that might spin up later (hence updating the AMI). I could also change the AM

Yes, in fact that's what I do! The issue is I need to account for any new servers that might spin up later (hence updating the AMI). I could also change the AMI's "user data" to run pip when the instance loads, but I'm not 100% confident it will always run without errors. I feel better doing it manually and baking it into the AMI. Personal taste.