The three trainees / newcomers are a problem, I admit - I think you have to assume that this is part of Coulson's master plan, and that Coulson, May and whats-his-name (possibly not a good sign I don't remember what he's called) are there to take the load until they get up to speed. Alternatively, that the whole operation is a false flag, and has been set up to fail in a way that benefits SHIELD.
