I also think it'll be very unrealistic to make new board for MorphOS alone that should catch up to modern desktop area domain. There are too many obstacles on the way.

But I could imagine a simple real low cost board could be interesting. Look to raspberry pi and the many other ARM mini boards. A similar approach with a ppc in it instead of an ARM could be of some interest.
It'll be not as cheap as those tiny ARM boards, but price is not always the only factor (as long as the price doesn't exceed sanity as it is the case with X1000).

A few years ago I thought that with the 5125 some interesting stuff could have been done - but that'sprobably too little by todays standards, even for a 50 EUR board. But some low end QorIQ could do the job (but for MorphOS compability one not having an e500v2 core wich limits the choice within the low end domain virtually to teh T1020 and T1022). Keep many I/O lines accessible, QorIQ has quite some network power, and maybe put an FPGA in place (adds cost of course, but offers some benefit over the ultra cheap ARM boards) and you'll have an interesting tinkering device. A little geek toy/dev/router board, quite a bit more than a pi, but less than a normal computer. And geeky OSes.
If I had some venture capital I'd try that. But I haven't...