I think you're trying to hold a desk together with a single screw.

I'd delegate; one PIC to manage the RF peripherals, one for both LCDs, and so on.

A USB master PIC would poll each slave in turn, managing the exchange of data.

I was a mainframe programmer in COBOL. PC programmers make fun of such an archaic language but it taught me to think modular. It makes for more hardware, sometimes duplication, but it makes robust systems.

Robert