While we over in NA are getting it in chronological, I think Japan is getting Alternative first then Progressive. Or at least that is what I've heard.
As for Alternative episode itself, it is good. As an alternative (I really don't think this is set in the same universe) to the first series, season 3 has some parallels to it while being its own thing. Kana and the rest of the girls probably don't want to grow up while Naota wants to but was having issues.
For Haruko, there is no need for a big introduction for Haruko. We as the audience know who and how she is. Save the creative and actual budget to the later episodes.
As a side note, I was doodling with my FLCL and Gainax/Trigger references out when the episode dropped. I found that to be a funny coincidence.