We should attack and defend as a team. The problem last season was that we didn't, we relied too heavily on individuals (De Bruyne) to create something out of nothing, especially for the first goal in games. The two previous seasons we had a variety of patterns of play, we would rotate the fullback, #8 and winger on occasions, we would create overloads in central midfield, we would drag teams into a press and go long with the pace we had on the wings. This season that's happened infrequently, we have played slowly through central midfield with very little movement (in comparison to previous seasons, not in general before anyone flies off the handle), then given the ball to De Bruyne in the hope he can hit a pass only De Bruyne could hit, or given to Sterling and Mahrez in the hope they can dribble inside and shoot. It's been predictable and boring, once the first goal has gone in its a different story because defending teams open up a bit.
The "defensive mistakes" theory is bit of a myth, yes we're guilty of defensive mistakes just like everyone else but this rubbish that is spouted on here like it's 25 times a game is simply not true. Our style of play requires fast and intensive pressing from everybody, we can carry one player at times but this season we've been carrying two or more (Silva, Gundogan, Aguero, Rodri, Mahrez) in the majority of games before the ball even reaches the defence.
If we get the "pressing" back to the level it was the previous two seasons, the defence won't be as exposed and our defenders won't be left isolated 1vs1 as many times, meaning even less defensive mistakes.