Hi there,
You can put hotspots and radars onto the map viewer (as you've already said).  How about having your standard map viewer showing the map and adding a hotspot to the area you wish to see in more detail.  This hotspot would launch a pop-up viewer.  You could make this look extra smooth (no pun intended on this forum!) by putting a box around the map area in Photoshop and having this boxed in area as the clickable hotspot. 

Not sure how clear this is but yell if you think its a possibility but need more info.