I like Bastos, he'd do a very good job here. He's not a top 5 left winger in the world but from what I've seen (which isn't that much to be honest), he is tricky, fast, has a very decent shot, works for the team and his stats back him up nicely. Overall a very, very good winger.
I'd rather go for Hazard, but it's not a Pepe that we are dealing with here. We need an exciting player that puts us on the limelight though, that's for sure, and that's why Aguero is a necessity. Beck and Ziegler will do a good job on the flanks and free up funds for exciting players up front.