Google : Shoot first, ask questions later
thunda, I'm sorry to say so, but it sounds like shooting first and asking questions later is what you
have done. We're now trying to sort out what questions you should have asked.
For one, the entire site should have been blocked from spidering until you had it thought out, well structured, with good content, etc. This has always been true. IMO, it's been even more true since Panda and Penguin.
As for the initial rankings, Google has tended to give new sites a honeymoon period. In the past, Google has done this to give new sites a shot at establishing themselves. I'm sure that the mechanisms for this have varied over time, but, since the Caffeine infrastructure, Google has pushed freshness. So, you got indexed, and during this time you tripped some filters.
From my brief reading of this thread, I'd say that your initial drafts contained a bunch of old timey, manipulate-style SEO tricks, and those, together with thin content and various structural issues, got you dropped way down.
One of the mistakes I see that might have confused Google quite a bit was your random post menu. With or without the <h3>s, randomness can only lead to confusion.
I bring some of this up because to Google it may have looked like you were a potential spammer who tried to change things that weren't working. Google does have a mechanism to detect that and to apply further penalties/filters to confuse those trying to game the engine. See discussion here... Google's Rank Modifying Patent for Spam Detection http://www.webmasterworld.com/google/4486158.htm
I don't know whether this is part of your problem, but the more you fiddle with your site online, the more it's likely to be seen as attempts at manipulation.
The history of the domain you bought (perhaps the first thing you should have checked), probably isn't helping matters. I'm sure it was one of the flags that set off some alarms. Possibly some of the old links are still alive, which maybe is how you got indexed so quickly.
I'm wondering also about potential issues like whether you're interlinking with your other sites, or how else you've built your inbound links, which I'm guessing would go along with this scenario.