I have only recently started looking at your spanish lessons (though I subscribed some time ago), and while I agree that regional series are probably a good idea in the long run, to a complete beginner in Spanish having so many lessons about some local differences is a bit daunting. Since I live in Europe, and in order not to mix things up too much, I've decided to focus on the Iberian Spanish series besides the regular Newbie and Beginner.
Unfortunately locating lessons from one particular series in iTunes isn't always easy, because all lesson titles more or less start the same. I know that I should probably try some smart playlists to filter out the lessons I want, but since you have the "My Feed" feature, which is really great, what about introducing the different regional series in it ? At the moment, you can only chose "Regional Spanish Series" on the whole (not a great help I think). Wouldn't it be much better to have:
-Regional Spanish - Peruvian
-Regional Spanish - Iberian
-Regional Spanish - Costa Rican
-Regional Spanish - Mexico
...?
And that could maybe also apply to blogs (basically easier from Spain or Mexico).
That way you could organise the regional series lesson to come just after the corresponding newbie, have a "standard" feed and "regional So-and-So" feed, etc... Basically have the flexibility that "My Feed" is all about.
Not having this is merely inconvenient at this time... but I think things may get very complicated when you have many more lessons, and also regional series branching into beginner (and higher levels) on top of newbie...