But I can't defend my stuff when I'm offline, which'll be fairly often as I play on other servers and play other games. Y:
that's pretty much the point. That means that you need a team, the bigger your team, the higher the chance you have of people being able to stay on around the clock to guard your stuff.
Or if you go the lone-wolf approach, that's why it's challenging.
Also Daedalus, I suggest you use one of those texture packs as well and base the server build around that. Vanilla minecraft textures just aren't good for the atmosphere you're trying to create IMO.