A lot of people feel the jet pack changed the dynamics of the maps. I rarely have used it myself, usually only on my first life if I get low spawn on reflection so I can get rockets and jet up for a couple quick kills. Tu' in the future may experiment with the jet pack, we will have to wait and see.
Yes I agree that MLG, of all games, should be ranked. They are typically our best and most competitive players and should have the "rank" to showcase their skill. Are you an avid MLG player and do you play in the Arena?