Lots of good ideas in here. The common theme is more cards for USB, Video, RAM and acceleration.
I no longer have an Amiga Im willing to part out and hack up. The one I have left is a prototype A3000+ that works and is restored. Its sealed and on display in my office.
What I think the best solution for all of us would be a total rebuild of a classic system like the Minimeg or FPGA. PCI slots and all are great, but you need drivers and support for far to many cards when going this way. Id like to see a board with everything we need on it. RAM upgrades being the only thing I can think of to have open for adding things on. Not including it on the board saves money and allows those on a budget to add what they can, when they can.
It should include:
Fast Ethernet
Hi resolution video with at least 512MB dedicated to it. (Video slot would also be ok but not the only way to get video out)
USB 2.0 at a minimum
IDE and SATA
SD Card slots
Ports to add new additions as they are made.
Classic hardware s getting old, and very hard to replace. Modern stuff is cheap now and able to emulate to near perfection a classic system far more capable than we ever could do on the real thing.
That is sort of my point with a new revision of a derringer.
think of it...
cpu board that fits inti the 68000 cpu socket of A500 and A2000...

it contains socket for 030 and fpu. (i have some collecting dust...)
network, ide with cf and connectivity for a cd-rom, ram expansion and usb..
all in one neat little card compatible with the scandoubler...
it would be nice.. really nice.

if this could be baked into a completely new amiga.... WOW