@RobertWPS @jared_fThis is a good thread, just chiming in with my current setup and what my team is moving towards. As mentioned earlier, Apple is deprecating NetInstall in the macOS Server app which I've used for years to get a "base image" on a Mac.
Current setup: Use System Image Utility in macOS Server and import a standard App Store macOS installer to create a NetInstall image. I don't join to a domain or anything fancy, but I do include a .pkg installer for Munki.
-Our Macs are enrolled in DEP, so Meraki pushes an enrollment profile to the Mac when we run through the Mac Setup Assistant. When we reach the desktop various profiles are pushed to the Mac based on tags.
-We open Managed Software Center (Munki) to install our remaining .pkgs and installers (including the Systems Manager agent)
Future setup: We just enrolled in the SM agent beta previously mentioned in this thread, the goal being to eliminate Munki for our other configuration .pkgs and app installs and just utilize Meraki. Due to Apple eliminating NetInstall in the near future you can create "one last" clean NetInstall image using the macOS 10.13.3 installer from the App Store. That should work in the foreseeable future, but will become burdensome as subsequent updates roll out and you end up "manually" updating each Mac during setup. Apple might have a fully fleshed out solution in the future, but for now I envision it will be like the iMac Pro where any re-images are based on an active internet connection and the recovery partition erasing the existing volume.