I actually quite liked the book, for all its bonkers aspects. Normally I'd suggest they could make a decent 'normal' movie out of it by toning down certain aspects and focusing it being about the artist's struggle, but seeing as it's Snyder I say he should dial the madness up to 11. Just have him flat out revel in all the speed-ramped rape and terrorism.
Michael Fassbender has to be a show in to play Roark. I mean, he basically already played him in Steve Jobs.