I'm too far gone from my last AD admin job (7 years), but I mainly remember how tightly integrated everything was. I could play that infrastructure like a fiddle!

The greatest thing about AD is that it's a "single pane of glass", all there in one tool. One example, I used RADIUS auth with Network Policy Server (NPS) to manage wireless access. Put users in the appropriate group, never had to think about it again.

One of the best parts was how easy it was to manage with PowerShell. I had on on/offboarding script that would handle a dozen pain points at a button press.