The ability to display up to 15 active overlays is absolutely great for route planning. However, there are recurring situations where the display color of the individual overlays should be configurable. This would make it possible to distinguish the overlays on the map during the planning process. Here are 2 examples where this would be useful:
[Example 1] You have saved several routes that you have already ridden in a specific region within a folder. That would be Overlay 1. Now, you receive a route plan for this region from a friend. That would be Overlay 2. If you now start planning a route that goes through this region, it would be highly beneficial to easily recognize in the overlays which sections belong to the previously ridden routes (Overlay 1) and which are potential alternatives (Overlay 2).
[Example 2] If you want to integrate sections of the TET into your route planning, it is advisable to check the TET sections to ensure they are up to date right before you start. To do this, the current route plan would be open so it can be adjusted if necessary. Overlay 1 would be the old TET GPX imports to distinguish them from the rest of the route segments. The new TET GPX imports would be Overlay 2. Having a different color would allow you to easily identify the old and the updated TET sections within the route plan.