While I may not be politically in line with the new mayor of Seattle I think his transportation mantra of mobility of people and goods instead of vehicles is right on the mark. The recently forwarded option A+ for the SR-520 replacement is a failure by that metric. Here's an idea that does meet that goal and saves billions at the same time.
Make the Montlake exit Transit/HOV only from 7AM to 7PM. Build the exit just like the Totem Lake flyer stop. This will keep the footprint only eight lanes wide and eliminate the huge wasted space caused by the clover leaf. If you do away with the break down lane built into the rest of the corridor the exit and flyer stop need be no wider than the bridge deck. Dress up the new overpass with plantings keeping the boulevard feel of Montlake between 520 and the cut. This would eliminate the costly lid proposed in option A+. The ramps returning to 520 from the flyer stop would be down hill to aid buses getting back up to merge speed. Unloading level with Montlake would eliminate the stairs for transit riders making the stop ADA compliant. Reduced vehicle count on Montlake would make transit connections with the new light rail station at the UW a breeze. The UW has been successful over the last decade at reducing the number of vehicles accessing the campus while steadily increasing campus population and employment. Time to take a page from the Husky play book and realize that more cars are not the solution to traffic congestion.