You also did something with the coast, it seems. Very minor, but also contributing to the "meet in the middle".

The tree changes definitely helped. The land icons look much more coherent now. The cities are still a little crisp, but I don't know how you could make them any blurrier without distorting them too much. I take back my suggestion to revert to the previous mountains. Meeting in the middle is probably your best bet. The cliff at the isthmus could use some blurring, to match the other terrain icons, even if it is technically part of the tower icon.