It just wouldn't work: deep, philosophical movies and the box office don't go hand-in-hand without prolonged action or cheesy comedy; anti-heores aren't usually accepted by the general public; rape scenes would make people get up and leave, regardless of how the protagonist fails to make-up for it, especially if people came expecting a movie like "Lord of the Rings" or "Chronicles of Narnia". The Chronicals are just too boring for the teenager market, too brutal for the hopeless romantic market, too slow for the die-hard action goers, and too blasé for the general fantasy market. The only people who would enjoy it would be fans of the series.
The only way the film can make profits is if they tear off the integrity of the first volume, condense or shy away from important scenes, for the mainstream audience. And I, for one, will not stand for it: the books deserve better than that. If the only way we can get a movie of The Chronicles is if the developers remove the deep, significant philosophies, then I don't want one. Covenant deserve better than cheesy one-liners, a character melodramatically screaming, "Noooooooo!" as another dies, exclusion of any of the scenes to fit within two hours, an audience with the ability critically think no better than a box of rocks, and people screaming, "Ahhhhh! Rape!" and "Lord of the Rings was better because they were all pleasant and gay. And the elves were hawter there."
Hollywood cannot do this, as its "All style, no substance." Indie filmakers might have a chance of doing it more justice, but unfortunately they aren't the ones producing this. If this movie is produced, it will either kill it's own integrity or kill its own profits. Either way, there won't be any sequals.