Actually, the highway ramps on the block are dead due to new ramps going in south of I-64, a change that occurred with the new ballpark.
The concept for the ramps west of Pet came out of the New Mississippi River Bridge studies and its related reconfiguration of the Poplar Street Bridge. Essentially, current PSB ramps to I-70 and Memorial Drive will be lost in order to double the ramps (to 2 lanes) from I-44/55, thus alternate downtown access was recommended west of Pet. But then, with the new ballpark, the 8th street on-ramp had to be removed. Thus, a new study produced newer options shared below:
New ramp alternatives
The yellow ramps to Gratiot were the preferred alternative. But you might notice that such configuration still doesn't provide for an off-ramp from Illinois to replace that to Memorial Drive. The on-ramp to Illinois will serve double duty for replacing the lost 8th Street ramp and future loss of Memorial Drive on-ramp to the PSB.
Also, the yellow alternative on the above linked image shows a new street and roundabout just north of the rail tressel, or just south of the existing intersection of 6th and Cerre, where the current "Last Missouri" or Broadway exit connects to the street grid.
What is now actually preferred is an intersection of Gratiot and 6th south of the rail tressel, with new signalized interchanges on Gratiot at 7th, 6th, Broadway and 4th, while removing signals from Cerre intersections.