I think the 2nd ep was more like filler than the 4th. Some interesting and important character stuff going on in the 4th ep.
ETA: I should say that I liked both eps just fine. Just that insofar as the 4th could be seen as filler - and I can see why you would say that - the 2nd ep has the same problem, and I found the 4th ep more significant in its character development. (And I'm not talking about the new characters).