Another reason why I think that there should be a lowering of the rank requirements for the current missions is because around level 25-30 (I forget) in XI, we were doing this:
http://www.youtube.com/watch?v=ycMoA...8D198E&index=4
Unless the new companies missions are supposed to go along side the story missions ( likely since the Ifrit battle topic has nothing to do with company missions) and/ or the rank 30 dungeon has a great boss battle.