Epic Good Time Funland!

So, I have this idea planned for my Bukkit world, actually a couple. I'll go into them in a bit more detail here. They are both large, ambitious projects that will take a long time to complete, and hopefully some of the other players on the server will join in too.
The first is Epic Good Time Funland (name is a WIP). It will be our Minecraft amusement park. There are a few things I intend to build there, and I'm sure more will come to me as time goes on. So far I've got ideas for having a roller coaster (what's an amusement park without a roller coaster), a "petting zoo" (although I don't know if I'll be able to keep hostile mobs from despawning), a mob arena (big top maybe?), a gladiator arena (for some real melee pvp action), a bow arena (like the mindcrack paintball area), glass maze (or some kind of maze, maybe hedge), and much more.
Obviously, if you guys have any ideas of things you want to see in there, let me know and I'll do whatever I can to make it happen. The plan is to do it all as legitimately as I can, but still using the Bukkit tools at my disposal. I was originally going to start with a flat world using a world-generator but have since changed my mind to start with a new real world and just clear the land. Would give me a lot more to do, but also a lot more resources to work with.
The second project I had in mind wasn't exactly for me, but I'm considering either creating another server for my son's Hunger Games, or creating a hunger games world on the Bukkit server for him to play with. I have a lot of untapped potential on my server right now, I could probably run at least 2-3 more servers on it and was looking into Multicraft, but I don't feel like spending the money on something I can do with just a little more effort.
The hunger games that my son is doing is all arenas he is building in creative mode with no special addons or plugins, so having a separate server for him to play with might make it easier for him to make sure he does everything he wants with that.
I look forward to your feedback with ideas and suggestions!