I think a world map will be very difficult considering that battles will more than likely not be started be random encounters. And really, walking around on the map would be quite boring if it weren't for the random chance of a battle.
Yna oui uh tnikc? Un tet oui zicd kad duu lmuca du Sin'c duqehc?
Yea but the overworld was pretty much useless. There was usually only 1 new place you could go to and it wasn't really anything different than what we have now. Atleast now it doesn't look stupid with a giant sprite walking on a miniature world map >_>
Although I must say Dragon Quest VIII did a brilliant job with the overworld. They combined the best of both old and new.