Consider a USB FIFO, such as the FT245. It's faster than serial over a UART and considerably simpler to configure. (On both ends: the USB side appears as a USB serial interface, but it doesn't care how you set the baud rate, stop bits, etc. on the host since it's a parallel interface.)

I just ...

Let's see if I can manage to remember all the questions to answer.

I plan on using the W65C02 CPU for this project

The way the memory map switchover will work is the ROM will contain the startup code, possibly device drivers, etc... enough that the cpu can load things from external storage. The ...

I am currently getting all my ducks in a row on the initial design choices. Since I am new to all of this I figured I would post my thoughts here to see if I am missing something.

I plan on using the ATF1504A to handle address decoding. I was originally going to use the ATF22V10 but due to ...