Well, i don't see why we shouldn't be invite-only. Like BK said, we wouldn't get a ton of app threads. Or, we could have one app thread where people could apply with a low chance of getting in. Say, you'd write on the thread "If you have been invited post here who invited you and fill out the form, if you'd like to apply, fill out the form and wait for an answer." or sumthin. That way, if someone who would be a great addition to raid wasn't invited, he could still TRY to get in. If we actually like em, we let im in, if we don't, well you know. That way, we'd be predominantly invite-only but still leave the chance of being accepted through an app.
Just a thought :v