We have been running a private server for a while, but wanted to launch a new public server. We have been managing a few smaller, whitelisted servers honing our admin skills, testing out plugins, and learning the ropes. Our server is run by adults, not children, and we look to build a civilized adult and young adult Minecraft server community.
PVP, Creatve, and Adventure mode are available on a separate worlds than the main world, as we feel there should be a variety of things to do around the server. Other worlds will be enabled as we see fit, or are suggested, and added through Multiverse, with Multiverse Portals for travelling between worlds.
GriefPrevention provides a unique claiming system for protecting your creations. We aren't using Towny, but our players figured out a cool way to create player towns. Since then we have adopted a 3 separate player claims in a specific area including a town hall as a Player Town. GriefPrevention provides a great way for our users to easily protect their work from griefers. The latest versions also allow players to trade claims with others.
Aside from a few server plugins taking this out of the Vanilla category, we also run Spigot the Craftbukkit fork, which was formerly known as Craftbukkit++. It has some interesting performance enhancements that should help keep the server's resources lower as the community grows, keeping lag to a minimum for the server cost. It's apparently used by some of the biggest servers out there, so I'm thinking big from the start. Spigot includes a built in Orebfuscator in core, so the processing is much faster and more efficient than with the Bukkit mod. Spigot continues to amaze me.