Why isn't there a transfer between City Hall on the 
(and soon, 
) and Park Place on the 
?
It seems like it would be relatively easy. It's a very short distance between the ends of the two stations, at the intersection of Park Place and Broadway.
At City Hall station, you could put stairs at the South end of the platform going down, and continuing down through the very end of the west platform on the lower level. (Since diagrams seem to show the lower level platform being shorter than the upper level, perhaps that might not even be necessary.) Then a short passageway, emerging just above the north tracks in the Park Place station. (Park Place is very deep.) Park Place is double-height, with plenty of unused open space above the platform and tracks for short walkway over the north tracks, and then stairs down to the platform.
A transfer there would be very useful, allowing people to also transfer between the 
and the . Since the MTA opted against an in-system transfer to the at Fulton, this would provide a much-needed downtown transfer between those lines. It should make the under-used more useful to people with certain commutes. It would certainly improve options during temporary service changes on nights and weekends.
Thoughts?