Won't we all be happy when Glenn finally finishes his sub panel and we can get back to talking wood?

My plan involves a few different outlet box locations:

Some will be in a wall, stucco exterior wall, wood studs, drywall interior to be added after electrical.

Some will be in a wall, stucco exterior, wood studs, OSB interior to be added after electrical.

Some will be in the "ceiling" mounted to wood joists, no exterior or interior wall.

So, plastic boxes or metal boxes or a mix?