I don't think... that simple.
Hidden does in fact suck, because we're pretty much restricting people from finding us with no benefit. What if we have another zElite migration like we have every so often? They know our name perfectly well, but might not be able to find us, and be a bit embarrassed to ask specific people by PM to join. (That deal on page 577 of the barcode might be this again, or just them trolling around after leaving. It's a recruitment chance either ways, and we should take it)
Private and Open allow people to find us, so that's definitely a good thing to get if we at least go private.
However, from private to Open, we have to deal with a great deal of compromise. Private is pretty much the same we already have, but Open...
Open give us a few benefits. People can check in on our clan, see what they think of it if they're with that "should I join this clan" doubt. We can have people from other clans having talks with us, as if they were members of a guild. Advertising is done better if we go posting around public stuff that link back to us.
But there's the bad stuff. People may talk with us and never join. They may also take a peek at our threads and copy them or something. We also have to be more careful in moderating, because people outside might spam us, or people inside might start bashing other guilds...
So yeah, I don't think "change to private/open", I think "Ask everyone what they think before doing anything".
I, myself, think we have nothing to hide.