This is tough to answer with total brutal honesty, but in my opinion, many people want Guardian and above because they think it might give them a "more free" experience with the powers that come with the job, only coming to find out that the amount of work that being a Guardian actually entails gives what's probably more commonly known as "Admin's Curse." Any (good) admin on any (reasonably sized) server can tell you that once you've chosen to be an admin, you've effectively written off being able to 'just play' the game for the majority of your online-time.
Now, lately, the server's been quiet, and I think many of us have enjoyed it in a way because we've been able to get back to some of our personal projects. But the fact remains, when we're having a busy night, there are always people needing help. Some people can handle this, some people can't, and I think a big factor of being an admin is age and experience. Simply put, when you're in your 20s+, you've seen every type of internet-personality there is, and you have experience dealing with all of them. Some of our admins don't understand when they're being trolled, some can't handle the absolute ignorance of new players, others don't like conflict very much. Mag and I have learned much over the past year, in terms of what we like and don't like seeing in admins. It is probably for that reason that you haven't seen a great deal of promotions lately, despite the fact that many of our Guardians don't play much anymore (or at all).
Those of us who have remained have a clear and vested interest in the present, but most importantly, the future of the server. But even we get bored some times. That's why I try to introduce new things to the server when I can, but some things I work on are at a scale that just working on them at all sucks a huge amount of time out of me. The RP event, I can promise, will be epic and more awesome than anything the server's ever seen, but to accomplish that, the amount of work that is required to produce something of that scale is tremendous. That's why you're seeing little silly things like arenas being introduced. It's something I knew I could make quickly, that would be fun for the server, and that isn't as boring as trying to fix asy bugs :>
Anyway, rambled a bit, but perhaps this shines a light on some things.