Helping to prevent netdecking? Sorry, but I don't see it here. If anything, it would condense the 40 odd Metanite/Delta/Flygon threads that last a day or so in the deck help section into one area. I use the other site's archtype section more for a starting point and a strategy review rather than a netdecking reason, but that might just be me. The point of it is that people use archtypes, having somewhere here to formulate ideas about those decks, how to evolve them, how to counter them, how to cover their weaknesses and exploit there strengths is what an archtype section would be for.
As for what decks deserve an archtype section, that would ovbiously be up to the Moderators of the forums (who should have a good understanding of what the current archtypes are at least a little bit). I think it would help the site by keeping people here rather than switching from one site to another.