The concourse has been looking better lately, although I would be the first to say that it has a way to go.
Aside from housekeeping, I see two basic problems in the concourse: It is very difficult to maintain orientation, and the sense of being cut off from the outside world can be oppressive.
Ed Bacon's proposal, as I understand it, punctured the carapace and gave people underground frequent glimpses of light, air, and the upper world, while showing the upper world glimpses of the activity below and serving to unite the two levels. Unfortunately, this vision was not realized.
I think a lot can be done with what we have. First, current wayfaring signage leaves something to be desired, including a reference to JKF Boulevard.
Second, Bacon's idea of piercing the veil between the two levels -- terrestrial and subterranean -- could be a significant part of the Love Park redesign. I've never understood why the parking garage is so hidden away, almost as if we were ashamed of it. The entrances could be portals of light for the underground and also give the park dwellers a sense of the amazingly complex transportation nexus that is flowing beneath their feet.