@bloodline:
This is pretty much the situation with all Amigas. If you expand them to the max not much of the original motherboard will be used. The motherboard will be used for some various I/O like keyboard/mouse, ROM-socket

and as a means of compability with older software.
Though there is no need to go all the way to the max when expanding a system. A PCI-board with a graphic-card and a network-card would a reasonable expansion

.
And you have to admit that it would be fun with PCI-slots in an A2000!

).
/Patrik