It's exactly what I wrote earlier - taking better care of the ball would be a massive help. However, Gana was very good at keeping the ball, so we'd also lose that, too.
In terms of passing, he was accurate, yet also progressive. His passing % was 87%, yet he led the team in forward passes and led midfield by quite a bit in forward passing %, led the team in final 3rd passes & 2nd in final 3rd passing %. Most progressive passes per 90 of anyone in our midfield.
He didn't lose it off the dribble often, in fact he rarely tried to beat anyone off the dribble, but had one of the highest success rates on the team when he did try. He was 11th on the team in what whoscores calls "bad control per game" and was 9th in being dispossessed. Considering he led the team in touches, that's quite good.
FYI - I do think the biggest culprits in the team in terms of bad control - Richy, Bernard, Gylfi, Walcott, DCL - will improve either by getting better or being replaced. Same with those being dispossessed - Richy, Gomes, DCL. But having a CF that can hold the thing up a bit would really help.