For me, a new accelerator with the following:
1) Full 68030/68060 with FPU.
2) Level 2 cache (I've read that this is possible).
3) Fast DMA SATA.
4) Can hold up to four gigabytes with new sticks (you get 4 gigs-16 megs of free memory).
5) DMA USB2.
6) DMA ethernet, either wired or wireless (option).
7) Part of the memory has a second bus for the DMA devices.
So, that's it, unless I've forgotten anything

Another idea would be some sort of system that allows you to connect multiple A1200 mobos through the CPU slots, so we can have dual view and multiple CPUs
