the problem with the EU is "top thisism" is rampent. it's particularly bad with some writers (Kevin J Anderson comes to mind) but it's basicly a matter of "well to be impressive this new thing must be better then all thats come before"
Pretty much. Perfect example is the Yuuzhan Vong. They went so far left field to introduce a new, overpowered galactic threat that a lot of people (at least a lot of people I've spoken to, not trying to make a generalization here) simply disregard it from EU canon entirely.