Well I'm on the next stage of the project... hooking up hardware so it'll update color at a per pixel frequency instead of per tile.  My 8Mhz clock speed is too slow to update per pixel; so instead my plan is to preload the tile's color bits into shift registers and have the shift registers spit out the on or off bits each pixel.  While they're spitting them out, I'll have a second set of shift registers I'm preloading the next tile color bits into, and so on... basically double buffering per pixel tile data through shift registers.

So I'm starting simple by using only 2 shift registers - which will allow me to output a single on or off bit for each pixel.  Ideally this works and gives me per pixel white or black (on or off), once it works I can expand it to the 8 shift registers I need (4 bit color and double buffered) and have my full 4 bit color per pixel.

Here's the breadboard...

Looks kind of messy, but the concept is simple - you can find the schematic under my github at:

https://github.com/mcferront/ss_minnow/blob/master/PCB/MaryAnn_1bit.dch

It's not worth posting more right now because... well nothing works.  It's not even responding back to The Island (my motherboard).  I'll start debugging tomorrow, basically by hooking up LEDs and try and figure out where it's freezing.