A version of RC with a level editor, etc, or something of the likes as a standalone app on the DS would be phenomenal.
That's what I would like to see... PSP is not so popular or fun to hold in your hands. It is a player interface only... the DS has technology that facilitates creation and management as well as player use.
I understand that it's not really fully capable of running Graal whatsoever. It's better suited for many of Graal's needs though.