We need consistency as a beta before we can go public. Even before moderators are chosen. Imagine a new user coming to the site, posting a question, and half the community thinks it's great, the other half thinks it's out of scope. So The user goes on chat (this is a smart user) and asks if the question needs improvement. There are a couple moderators populating the room. One says it is entirely in scope, another says it's out of scope. They both have meta posts to support their opinions, but both posts have been both upvoted and downvoted by the divided community.
Anyway, going public before we're ready may have issues, but we need to agree as a community on what our scope is. We're in this processes right now. We asked 'What is a lifehack?', and the community voted. We have to go with that set scope, unless there proves to be a huge issue from it, which we must discuss and work through as they come up.
A wide scope doesn't mean destruction, unless we can't handle it. As long as there is general consensus in the community, and there are solid, clear guidelines that are easily apparent to all potential users, a wide scope isn't an issue.