Overall, I like your team. Plenty of pop, but like everyone before me has said, you need to watch out for avg. Also, you only have one truly reliable source in SBs: Ellsbury.
Staff has plenty of upside, and funny enough, a friend of mine was asking me about Cole being his ace. I am not sure he is there yet, and I think Julio is going to be your best pitcher by season's end. Cobb is solid, too; however, this is definitely a boom or bust situation.
I would maybe look to trade for a more solid number one, if possible, but give the potential of your staff, I would leave it as is now; you can always trade power for pitching down the road.