Now that you are making landscape changes in Eriandor i believe that is a good opportunity to have a look at the region of Wildermore. I understand that before Wildermore released those cliffs had the meaning of boarders on undeveloped area but when the Update 11 - Treachery of the White Hand was released the cliff boarders did not changed. Rohan is suppose to be a huge open area and having that kind of cliff wall area make it look weird. I believe that if middle earth had such a fortified area surrounded by cliffs then kingdoms would definitely made walls in the small opens to secure the farmlands and the lake of Wildermore. People of Wildermore would definitely stay in siege for ages there. Also Cliving could easily lost from a siege because catapults and ladders could come from above the cliffs.
Conclusion, as you can see in the image with the red mark i believe that all the south cliff walls should be removed from the game and replaced by open hills where we can run freely in our war steeds. You can keep the altitude by using smoother elevation to connect the area with east Rohan and waves of Fangorn (will make Fangorn look even bigger and continius). Also Open the road between wildermore and Great river. The cliffs in the North can still boarder great river and Wiildermore since river erodes the landscape and does make sense.
Small things to mention.
1) The small cliffs that include the drake cave between east Rohan and wildermore can remain
2) The cliffs that boards Cliving can still remain in game although i believe that Cliving should be fortified with walls instead.
3) The altitude should remain so we can keep the nice view of Rohan.
The actual connection between Rohan and Wildermore should be open free walking space.Questing from west Rohan the cliffs looks like the wall of game of thrones in the distance xD.
P.S : I know that the game need other things to Fix first.