Hello you'd better wait for fpga arcade , the 060 addon by Yagube is for it and not for the Minimig...
If you want a Minimig ,ARM is , to my point of view , needed as last firmwares are now difficult to add to the original Pic , and last firmwares are now at 99,5% in term of compatibility with games.
Adding to that the extra 2meg of ram , you'll be able to run a nice classic workbench and whdload , but is it really needed as ADF run really well ?
You can see thid thread : http://eab.abime.net/showthread.php?t=52639
Hope that will help you.