I ran it previously because I came from that world and I just thought that's what you did. I was less Linux-y then. It's really overkill for such a small network but if you want to learn AD then it might be worth it. Personally I hope to never look at AD again but alas I need moneyz.
If you do decide to run it make sure you enable profile caching in group policy, it will prevent you from being locked out when your DC is down. Also if you have laptops you can safely bring them outside your network and they will still be able to log in.