If your were hoping for a more user friendly mission editor...
Will the mission editor change and what new things will appear in the map editor
The mission editor will not change much at its core, because it is already considered a powerful visual tool for complex scenarios, albeit with a high entry level. From the point of view of creating complex scenarios, for example if making something like Tactical Air War, it is definitely the most convenient tool compared to competitors. The main development concerns the map editor: now you can edit the height map, rivers, roads, cities, textures, and other elements directly in the tool. This should simplify map creation and potentially attract more creators from the community.