With SAS Grid Manager in 9.4M6, the deployment of SAS Workload Orchestrator and SAS Job Flow Scheduler are through the SAS Deployment Wizard and you should be able to use its unattended install feature to install your deployment.
Previous versions of SAS Grid Manager (now called SAS Grid Manager for Platform in SAS 9.4M6) had the installation of Platform Suite for SAS as a 3rd party install prerequisite for the SAS Deployment Wizard so SDW's unattended install feature would not be able to be used for Platform Suite for SAS. However, the installation of Platform Suite for SAS on Linux is a command line based install that could probably be automated without much trouble.
If you install & configure to a shared file system (as opposed to a local file system), new machines may be able to be added/removed without having to reinstall/redeploy your software - you would just need to start the necessary services on your new machine.