I'd be interested in trying out your map editor. Are you planning to add wilderness editing too? that would be really cool...
I have already reverse-engineered P1&3 savegame formats (http://amigan.1emu.net/releases/rpg-form.txt
) and made a character editor (http://amigan.1emu.net/releases/PCE.lha
), you might be interested in them...
There appears to be a X68000 version as well. I'm guessing this would be the best version.
At over 40Mb in size, one would hope it was the best version