I really would be against a mini-games server. It'd require a whole new shitload of technical support, admins, and split up the free playtime of moderators even more.
However, I'd be happy for a small mini-game or two in the lobby as Difficult1 said. Nothing special, perhaps a parkour course above, perhaps a small punt arena below the lobby itself. Sure, mini-games are a core component of Minecraft as a whole, but that doesn't make them compulsory - nor does it mean that nerd.nu has to immediately adapt to it and become like so many other servers out there.
Perhaps in the future when more players are very keen on it, I'd love one.
But at the moment it won't see enough use or encouragement, that's my opinion at least.