Anyway, this sounds good, but for the love of god take a tip from LucasArts and do not make this game unwinnable. I've always wanted to play some Sierra games, but I could never get over that infuriating design flaw.
I don't think that was a design flaw, per se. A lot of people don't like it, but that's how they designed the game.
Anyway, they have talked about that (in podcasts and on Twitter) and seem to understand players' feelings on that. So I'd imagine they'll try to work with that in mind.