I was excited to see this discussion this morning, because I am of the mindset that this will change downtown, by attracting corporate business back into the core and thus causing other retail and residences to follow. I have no industry knowledge, just that of a commuter.
Though I like the idea of condensing the current plan, my reasons are purely for the more TOD in the area. As a person who uses transit all of the time, I don't see a major issue with the layout. It is pretty straightforward, get off one mode, go to a packed main corridor to my next mode. The only real drawback is walking, but how many people are going to go from Amtrak to Greyhound? When I go to our office in Stamford, my route is Amtrak from Jax to NYC - Penn Station, then a 20 minute walk or two subway trains to Grand Central where I board Metro-North to Stamford. So, that is certainly a harder transfer than this station would provide. And remember, our destination is not the center, this is just a pass-thru on our way to somewhere else. Also, I would imagine that it enables areas to be shut down, for instance Greyhound has people in it 24 hours a day but JTA areas would become homeless sleep centers once the last buses pulled out if they had access to an all-in-one area.
As for this design, I think the final will need to have the bus portion redesigned. Out of curiosity this morning I went to the Rosa Parks/FSCJ Station and sat for a few minutes watching how things worked. I noticed two things, a lot more people are utilizing the Skyway than I remember a year ago, which is a good thing. Also, in between 7:45 and 8 am I counted 27 buses that entered the east side of the station and each stayed for about 2 minutes, (two were there for almost 10 minutes and the driver of one said he was running early and had to wait to continue on, I felt bad for the people trying to get downtown that did not know their bus was 10 minutes early). Now if you combine that traffic with Greyhound, and with cars coming in and out of that parking lot, it would be a gridlocked nightmare during peak periods. What happened with this design from a few years ago? Is there a reason this won't work?
http://www.metrojacksonville.com/article/2011-jun-ten-affordable-fixes-for-transportation-in-jacksonvilleAlso, if you left the layout as JTA has planned it, and remove the convention center, wouldn't that space be needed for commuter rail to the north, west and southwest?
But overall, great presentation and hopefully will urge the right people to at least think about other options.