There are many problems. Whatever McCarthy's shortcomings he did win one championship and had them in the playoffs many times. They gave that huge contract to Rodgers and just like so many other teams who have to break the bank for the QB, there is nothing left to pay the other position players. See the Ravens... the Lions... Brady has restructured his contract numerous times. On the bright side Rodgers does have a couple good years left so there is hope for The Pack. A receiver, an RB, shore up the D and bingo.
One of the few weaknesses that Rodgers has is that he does not read the defense as well as someone like Brady hence he is always scrambling around, for good sometimes, and for ill other times.
The constant scrambling also leads to him getting injured often. He needs to stay in the pocket more.