I'm in the middle on this. I love that RED is proposing such a huge development and planning to do so much to revitalize the core, but at the same time I understand the arguments of the other side who say that RED got a full city block for free and needs to make more public use out of it.
I don't have the graphic design software or skills to draw what I have in mind, but I'd like to see the open space split equally between block 77 and whatever the next block east is. The open space would essentially be split down the middle by Central Avenue. The space would essentially be a diamond shape, with the current design of Block 77 remaining mostly as is, but angling the sides of the two towers on the middle block to create a larger space in the middle, almost symmetrical to what's across Central on 77. This would place the pedestrian bridge over Central essentially right in the north middle of the open space and allow it to be used as a stage for large public events. The retail all around that space would be two story, which means that it will be ringed by a second-story walkway all around the site, creating great viewing spaces for any events.
If someone wants to draw up something like that to make it easier to visualize, I'd love to see it.
Edit: Here is a VERY CRUDE representation of what I envision: