Wait a sec! You are using default MapTool drawing tools to make those maps, aren't you? That's pretty darn awesome.
I am, and thank you for the compliment.
My primary objective with this campaign has been to minimise my setup time. My free time at the moment is somewhat squeezed, so trying to get some role playing in is quite difficult. Which is ultimately why I am playing D&D Essentials instead of Hero System. With a downloaded campaign from WotC I find I can build the maps very quickly (even the dungeon levels), import the monsters into Rumble's Framework with little more than a copy and paste, and all the other resources I may need are no more than a Google away. Job done! EDIT:
The other reason I've done the maps this way is to keep things light. There are some very nice maps available for free download for this campaign, but they are often quite large. Since we are playing entirely remotely and the quality of peoples internet connection has significant variation, I am testing that everything loads quickly and everything can be run on 256M. So "light" maps are very important.