I'm skeptical that a "wall of buildings" will cause significant issues for WNSH sending a decent signal into central L.I. The proposed ERP is 40,000 watts. The signal map filed with the FCC does show a small bend westward, near E. Babylon. That may be the extent of the signal blockage.
Proposed 94.7 Signal: https://www.fcc.gov/media/radio/map...y=NEWARK&state=NJ&fileno=BPH-20190213ABC&.map
The underlying database on which that coverage map is built shows only terrain, not manmade structures. The underlying terrain, of course, is reasonably flat from the Meadowlands across Manhattan to LI.
The real-world RF environment is anything but flat. And just throwing sheer power at it isn't necessarily the answer - it has the danger of creating even more multipath as the RF bounces around and through the urban caverns.