How to manage company Macs?
macOS Server and Apple Remote Desktop (ARD) are just two of the tools used to administer Apple computers in or organization.

You could use macOS Server to sync up with Active Directory, but in my experience, you can simply join each machine directly to your AD server without the intermediary (in other words....it's not required)

As for ARD....YYMV, but personally, I would rather use custom scripts to push out applications and updates

Apple has an excellent service called Apple Deployment Programs which helps you manage everything from AppleIDs to macOS and iOS deployments.  Contact your Apple business rep to help you set up this and your AppleIDs specific to your organization.