Base Camp already does a lot of things I like of Mapsource. Thumps up!:)
Still some things to make it even better:
-the coordinate display of the cursor should be at the status bar below the map as the marked waypoints (WP) and not near the cursor
-the navigation bar (step,zoom,rotate) on the map should be customizable, i.e. smaller, without rotation for 2D, or included in the status bar
-It should be possible to customize the appearance of waypoints on the map, i.e. only symbol, symbol + WP name, symbol + geocache name (as right now)
-WP names in WP list on the left should be customizable as mentioned above, too (Geocaching name / WP name)
-more columns in WP list, i.e. cache size, difficulty, terrain...
-Possibility to read WP info/description directly from GPX contents, i.e. geocache descriptions, for times when offline
-The subject of custom WP symbols has already been raised, only for completion;)
That's it for now. Hope anything of this suggestions makes it into the next release.