I think we're lacking a bit on this team, maybe not talent-wise, but certainly size, strength and athleticism. Facey has the skills to be a great CB, but he's a bit diminutive in stature and can easily be pushed around by guys like Kamara, Drogba, other big forwards in the league. It's tough to give up some of that size in the middle.
Tommy Mac, while his work rate is wonderful, has great vision and some good skill, is one of the slowest, least athletic guys I've seen in MLS recently. Not saying there isn't a spot for him on the team (or Facey for that matter), but I would give him up to get more speed in the lineup.
These are just two examples, but I think there's a bit of a deficiency in pace for this team, especially on the wings. A guy like Angelino has the speed to be a threat outside, but needs to be mindful of his positioning. You'll see guys like Accam, Oduro, Oba... they all are unmatched while on a give-and-go or making a run. I'd love to have a few guys with speed enough to finish off a play. We've really missed that from Shelton. And the Mac, Pirlo, Lampard midfield really puts us at a disadvantage on the counter, especially considering how often the ball stays in our defensive end.
ETA: We need more physicality on the offensive end, too. Aside from Frank, we're really only throwing a bunch of 5'9" guys in the box. We're really lacking size up from that Nemec was supposed to remedy. And now he's been MIA other than at practice.