So the new lane through the bottleneck section will be a managed lane - some or all users will pay a toll to use the new lane during rush hours and other busy periods. They will also convert one existing lane between Austin and Racine to a managed lane, so virtually the whole Eisenhower from Mannheim to the Loop will have 3 free lanes at all times plus the managed lane. I don't think they've decided on the operating rules for the managed lane yet, but it will be some combination of tolling and carpool/HOV restrictions. This will also limit how much extra traffic results from the expansion project, so that's a good thing.
Yes, the project will include the funky new interchanges at Harlem/Austin shown in that rendering.
The regional trail will be continuous from Desplaines to Austin where it will connect to existing paths in Columbus Park. It will run along the north side of the expressway trench, you can see it in that rendering. It will be mostly a street-level trail, but at the sidewalk level so better than an on-street bike lane. Kinda similar to the
path that the city built on Roosevelt at Wabash. The trail might fly under the interchanges at Harlem and Austin, but I've seen it shown with an crosswalk across Harlem and Austin in some documents.
Not shown in that rendering are a series of sound walls that were requested by the community. Federal regulations now require sound walls along new or expanded highways in denser areas unless the community declines. Hopefully they are nicer than the god-awful sound walls that IDOT put in through Norwood/Oriole Park.