I've been thinking about versions of this ever since I was at AngelList.
A lot of companies don't get a good look from investors because they don't understand investor expectations. "Negative signals" kill pitches. It might be a sign that the system works – but I suspect it's an inefficiency. Not every company has access to the kind of advice that YC and other accelerators provide.
The underlying principle is that the bulk of pitch mistakes are common. So Deck.vc reviewers can have a checklist of the most common recommendations and generate the bulk of the review really efficiently. That's what makes it possible to price this like a product, instead of consulting.
My goal is for Deck.vc to be of value to every founder who goes out to raise. Feedback greatly appreciated.