ArcGIS Online doesn’t make it incredibly clear that you can create a custom basemap for use in Map Viewer. Within the map viewer itself, there are small adjustments you can make from the basemap details and settings panel, such as darkening the hillshade layer through...
Do you feel like you spend too much time on reordering and adjusting transparency of layers just to show overlapping features, such as hillshade? If this issue is still haunting you, then you must not have moved on to ArcGIS Pro or the new Map Viewer, yet, where you...