Based on what I've seen sell, I disagree. The larger books, especially those in hardcover, tend to do better. How many books even hit the 64 page run these days? Heck, even 96 page is on the light side of things. When you need a 128 page book to cover a minor race in a setting like the Scarred Lands... well, the days of the 32 page book are over, the 64 probably not too long to go.
I do agree that not everyone has the funds to drop $40 but if you haven't bought it by now, you might not have say, because it wasn't in hardcover. And yes, I have friends who've avoided it for that reason. A deluxe edition might not sell at all but based on other 'revised' and revisioned books, including Dream Pod 9, not to mention the various Ravenloft books, it looks like that's the way to go.