The Link Project and Lower Zone Cursors option is inspired. Unfortunately there is no way currently to have the linking applied to the tempo editor or the stand-alone key editor.
I don’t care if the tempo editor is included in the lower zone, although some might find that an attractive option. What I really would love to see is the ability to link the views in the tempo editor and the standalone key editor. If the project window becomes part of that linkage, that’s just fine as well.