yeah sounds like a great idear.
Even though i am not there yet i was thinking of a new kind of world, not much different then those we are in now.
But this world(s) would be for the people who have completed alll character quest,(u go in this world at the level you were at after completion of quest or the current level you are at, which ever isd higer) in this new once towns are at a cretin level, perhaps there could be new challenges like protecting the bank from getting robbed, ect.
and new character quests too.
***cough cough cough***
I like the idear of farm i think we should have a jail to and perhaps a good black smith for our animals, i.e. good horse shoes makes em go faster