Some were. Some weren't. There were big complaints from some people about the multiclassing and what they considered broken system mastery/multiclassing options. Enter PunPun.
Not so much on the forums, but there was a silent (aka...not really silent, but not anywhere close as vocal as the m/c haters) group that complained about the CR system and how they felt it was to confining and limiting, too dependant on characters following exactly the guidelines of equipment and other items...and how it was easily unbalanced one way or the other due to party configuration and equipment and ability choices.
DM's complained about prep time with many focusing on the monster rules and how they had to spend so much time because they designed every creature like they would a PC (personally, I didn't do this, but I suppose many DMs did).
Ironically, it wasn't just 4e that delved into this territory though from what I understand. From what I saw with how Paizo worked with PF, I think these same items popped up with their playtests and they also tackled these things (albeit with a different method) head on also.