I think they will get stale very quickly like how keystones did.
The more unique you try to make the benefits, the more obvious the optimal pages become when trying to build for general purpose or circumstantially.
Just like with the WoW talent tree > talent matrix.
Yeah, it's cool initially because it's new and the selections you make have a more noticeable impact per selection, but it quickly loses its freshness, because the difference is that instead of people going to look up the "optimal" build, now it's just painfully obvious with a small amount of effort.