I'm thinking that if they still let you tap to select what to base the brightness on in this mode, they might be able to extend that to the focus so that it can

I'm thinking that if they still let you tap to select what to base the brightness on in this mode, they might be able to extend that to the focus so that it can work with non-face photos. Keep the part you tap on in focus (and anything else at that distance), blur the rest. Though that might not allow you to do independent brightness... Hmmm... Anyway, it's pure hope/speculation at this point.