The DDI at I-85 and Jimmy Carter Blvd outside Atlanta seems too compact. In addition the DDI reduced the travel lanes from 7 to 6 compared to the old diamond interchange while using the same width bridge deck (admittedly the pedestrian path was widened for the DDI but at the expense of a travel lane). Every time Google updates their aerial it just seems like there is a massive traffic jam at this DDI.
One problem I can see right off: the overpass structure is only 3 lanes in each direction (matching the original six-lane setup of the traditional diamond). Not enough space to handle the JCB through traffic and the left turning movements.
The solution would be to widen the overpass to add an additional lane or two in each direction to act as the buffer for weaving movements and allow for three dedicated lanes for straight on JCB traffic.
Also, I noticed that the through lanes in each direction drop a lane to the left turning movements before the switch back to conventional-side movement, meaning only 2 lanes go through before picking up the 3rd lane again from the right-turn entrance. That might be your choke point; need to widen to make it 3 lanes all the way through for consistency, and use acceleration/merging ramps at the on-ramp connection points for better merging.
Though, at this point, a SPUI with extended ramps would probably be more efficient here.