I am pretty sure that if you play economy you have at least wished for this command once. I recently sold my pumpkins with /sell all and it took my diamond armour, im really bad about this but i got to live with it I guess. I would like to see /sell undo so if you happen to /sell something that you didnt want to sell you can get it back! This is pretty much the whole suggestion and I hooe there gets looked into it! Bert came up with the idea of having /sell all not sell the stuff in your armour slots, that will help aswell!