Well you could mess with the crystal I guess but you would need
that 14 Mhz 020 to go to 28 (a little too hot probably).
What they should have done is put 68EC020/20 Mhz in there and
make it run at 28 Mhz and put at least 2 Mb fast ram as default.
Other mistake was 2.5" IDE connector as 2.5" IDE hard drives were
most expensive at the time , SCSI was much cheaper but 3.5" IDE
were way cheaper.
What they did is make companies who made software stick to 14 Mhz
2 Mb slow Chip Ram as default configuration and floppies.
If they did it that way it would be 4 x faster than stock A1200 and
software would be made for that speed.It's only 1/2 speed of 030/50
but it's 4 x fast as stock.