Reckon on a future Fallout, they should consider doing this, all DLC's are linked in the same story and each part continues it to the finale. I think it would work and create a lot of interest, they could have a 2nd Map, roughly half the size of the main map and have all new factions that can also be seen on the main Game map too once completed.

ring ring...

Beth: Whose there?

Caller: Obsidian here, we would like our dlc back!

Sorry I couldn't resist. But yes, that sort of setup is neat.

edit: If you didn't play New vegas, that was the overall theme of the dlcs, each one had its story, and each contained a smaller story arc that lead into the final dlc.

Ring a ding ding baby