VStack, ultimate data input system

Robots with GPS waypoints can develop a list of waypoints, and with more complex robotic systems this can be tricky to manage. VStack (vertical stack, I don't know why I chose this name) is a GPS coordinate manager, capable of displaying and scrolling through GPS waypoints, deleting, adding, modifying and route planning (eventually). Featuring more buttons than I can think of uses for, LED's, more buttons, a keypad, an LCD display (currently a 16x2, upgradeable up to a 20x4) and a analog joystick. The VStack will communicate via RS232 to the robot controller. Other modes may include, remote control, and some other stuff.

VStack is powered by an 18F4620 and a 18F2525. To give VStack more functionality, I added the 18F2525 to convert the Numpad (12 buttons, no multiplexing, ouch) into a simple parallel binary output (5 pin). To sum it up, there's a ton of inputs for this thing. A lot. Like 20 buttons. I could have this thing doing push ups practically it has so many I/O.

For GPS waypoints, I have up to 2048 bytes of EEPROM, and 112KB of flash memory, so there are a lot of waypoints possible. I may mount this in a 30 cal ammo can for added awesomeness and robustness.

Sounds useful, any idea how

Sounds useful, any idea how many GPS points you can store?
Also what PIC is it based on?

Updated the original post.

Updated the original post. Schematic available upon request.