Very good post, addressing many of the more relevant issues Cowon are presently plagued by (instead of the usual 'make an iPod Touch clone you Korean idiots' pseudocritique we most often get around here). I don't fully agree with you, though, because several of Cowon's present players are actually very very good, such as the i10 and the J3, and personally I feel they're heading in the right direction with devices such as the i10 and the upcoming Z2 (1.2 GHz gentlemen) and Android tablet.
You can bash the X7 all you want but the facts speak for themselves: It's the ONLY high-capacity alternative to the iPod Classic, and it does more or less everything better than the latter. Although it could have been a lot better, it definitely fills a niche.
What worries me is the persistent bass roll-off, the identical codec support between most players (with a few notable exceptions such as the D3, which is nothing short of stellar on this front) and the fact that they keep using the same DACs.