There would have been hell raised if someone else wrote Durance. The Codex would burst veins combing through the dialogue and showing how MCA's creation had been abused by Carrie Patel / Sawyer / whoever else. Honestly, the characters were MCA's babies, so it's best that they come up with new ones in their stead.
So, it seems that Vancian is gone at the moment, and they're looking into everybody having per-encs + unique power sources per class, like monks and ciphers from POE1. I think mages still get per-rest power source they use to augment spells, but it's not a Vancian system. I love Vancian, but I've long advocated for a more consistent system to avoid the clusterfuck from having some classes with Vancian and not others, and single characters having both per-rest and per-enc. In general, giving every class a power source seems like a good decision; monks and ciphers worked very well in POE1 and it gives design leeway to create unique mechanics for each class while having some consistency. Not so sure if the mage empower thing is going to be a good idea - you don't want too many empowers per rest, because then using them becomes busywork, you don't want mages to be too dependent on empowered spells, which just means they now carry a more messy pseudo Vancian system, but you also don't want to make empowers irrelevant. It might be better to just remove the per-rest schtick altogether - have rests be not quite as important as AD&D, and be forced by harsher health/injury systems, and then have character abilities be controlled through non-rest related power sources.
Edit: I think my gloss here is misleading. Reading further, it seems that per-rest Empower might be for everybody, and isn't designed to be superpowers - e.g. it'd be similar to 3rd edition empower spell. And it seems like spell levels and Grimoires are retained for mages. I'm not 100% sure what it's going to look like, but Sawyer seems to be pretty clear that the old 'mages have per-rest and others have per-encs' is gone.