Love the idea of losing the map when outside the base. It creates tension on death worlds trying to navigate around nests you forgot were there.
Although,
1. Remote view still functions when outside of the radar coverage.
2. Are you intending to include an optional sound effect?
I've got the C&C Tiberiun Sun radar online/offline sound playing in my head every time I drive in/out of range, which is licensed as freeware if you wanted to use that. Just need to add delay to prevent constant overlap when skating the radar edge.