I can't remember whether you've addressed this in your past posts, but this does far more than just injecting billions' worth of new investment in the area.
Most notably, it provides the space to untangle the knot of confusing grid connections on the east side of downtown. The Live Oak/Gaston/Ross/Pearl NE-SW connections are a ridiculous mess in part it seems because they're constrained by the highway bridges. Of course, it has to be done in a people-oriented way, or else you get a convergence of grids that will look like Lower McKinney East.
It kills the scary factor of going from downtown to Deep Ellum. As a college student, my friends and I would DART to downtown, then walk under the bridges at night to hang out in Deep Ellum. Frightening.
This could be what saves the Farmers Market -- or allows it to move to a more people-oriented area. Say, like, the open spaces provided in your design.
Regarding what naysayers to this plan might argue about making it difficult to get from US75 to IH45, give them the analogy that traffic engineers often use: Traffic moves like water. Highways like this are like rivers that have been turned into concrete culverts. There's no life, and there's nothing appealing about them. Slow the water (traffic) down, and it still flows, but it makes the surrounding land more appealing, more valuable, desirable to live next to, and most importantly full of life.
And here are the four slides addressing the issue with a bit of explanation. You should be able to enlarge with a click (fingers crossed):
1. Regional traffic circumvents the city via 635, 190, loop 12, 20, 30, etc. (That's a lot of highways btw). We dont want bypassing traffic near the city anyway clogging roads, polluting the air, creating demand for low level land uses like gas stations and quickie marts.
2. Local traffic uses, those headed to microdestinations, are filtered into the local grid. When ppl ask if this proposal creates a boulevard, it does not. Because the boulevard is already there in form of Peak/Haskell couplet. Both of which could handle 30,000 cars per day but only move 7-10,000. Way under capacity. And these are blighted corridors that could use the energy. Investors and developers look at traffic counts. These corridors are under capacity (Can you believe I'm actually asking for MORE vehicular traffic?! That's right. All urbanism is a balance). The key is disciplining the traffic. Spreading it around the grid so it doesn't overwhelm any one corridor, but also calming it enough so it doesn't adversely affect pedestrian activity and cross traffic.
3. Some disappears. All the traffic doesnt go to other roads. LA/carmageddon studies show 25% of vehicle demand disappears (some other highway removals or closures for construction have shown more and less reductions, but the basic principle stands). Instead, the traffic finds a new way around. It carpools, it takes transit, etc. More capacity induces demand. Less capacity reduces demand. As author of the book Traffic, Tom Vanderbilt tweet this morning, "traffic "cures" are like hangover cures: they're temporary, illusory, and don't address the root problem." This really speaks to the basic thesis of the entire presentation, study, and my approach and understanding of urbanism. Don't "move" traffic. Move the (real estate) market [so that it favors proximity = amenity therefore walkability].
4. Long term. The goal is to induce demand for living closely, proximity to amenity. And walkability as an amenity itself. The choice of transportation in terms of both route and mode is a form of empowerment. People can meet their needs without condemnation to car payments and volatile gas costs. Furthermore, it is precisely that choice that instills greater intelligence and adaptability into the system. Your mode/route choice is based on your needs/wants at that particular time, influenced by daily events. Is there a wreck? Are they filming something and have shut down a few blocks? Are you in a hurry or have time for a leisurely stroll. It's that ability to choose based on circumstance that improves overall traffic flow (of all forms) more than anything.
And lastly, the land sales and new tax base pay for all the streetcars and bike lanes we could ever imagine.