This is an awesome plugin concept, but I don't really see that this will work for 2.7.1. Also, I noticed that it might remove certain areas, but I didn't see where you could add those areas back if for some odd reasons you ever wanted them again.
I like the concept where you can HTML edit your own widget areas. I didn't fully test this plugin, as everything in each setting says only works for 2.3 or 2.5.
I really hope for an updated version of this. However, please in the near future consider just allowing the ability to "disable" areas/dashboard widgets, rather than removing them all together and allowing the admin to determine which default area should be shown.
Just from the look of this plugin, I am uneasy to use it, since I don't really see a way to hide, unhide, delete or remove block areas.