Hehe, 2 player PNC would be interesting indeed, imagine if we had played good cop, bad cop with Willie as 2 players… 
But I think there would be an even smaller numbers of buyers for such a game perhaps, unless it could be played as single-player also.
If he had the license: Loom remake + sequel. Maniac Mansion remake. Cult classics like The Goonies or The Lost Boys with same interface as TWP.
But beside from dreaming of that, if he makes anything similar to TWP type PNC I will back that, sadly I was too late to find out, otherwise I would have backed TWP.