The current Mars Navigator tool is limited to a 300x300 pixel map and takes a second or so to recenter the map. We are considering adding alternate mapping tools to the UI.
Using Java3D to create a more dynamic 3D map with a reasonable frame rate. The JMonkey Engine might be a good framework for creating this.
Creating a mashup with Google Mars that would be accessible through the UI desktop.
Using the Java version of NASA World Wind to create a dynamic map/globe. (Thanks to Paul Speed for this suggestion.)
Feel free to add more ideas to this page or add to its discussion.