Haaland has a very strong physics, and this makes him less flexible like suarez or aguero. The problem is that the team now knows how to stop him. They sent two CBs to guard him. This is also very effective in stopping him because Haaland is not flexible.
I consider Haaland is fast enough. But, flexibility is key to dodging opponents. That's why haaland is playing as a pure striker only.
That's why it's hard to find someone like CR7 at his prime. He is very flexible, strong, and fast.
Since his move to Manchester City, Haalaand was immediately able to adapt well to the Manchester City game and even in the first and second season he ended the season with the championship and also the status as top scorer, Haaland sharpness in scoring goals is no longer in doubt, but as you said, he is still still has weaknesses at the moment, Haaland has accuracy and speed in executing opportunities to become goals and he even knows enough where to stand when his teammate gives an accurate pass in a match, but like you say, Haaland is often invisible when he has to face big team and it is even difficult to escape when they are closely guarded by a tough defender.
I think that to become a better striker, of course Haalaand still needs to continue to improve his current abilities in supporting the flexibility of his movements and play So far, I have seen him play against big teams several times, Haalaand is often too close to the opposing defender so he often has to rely on physically to win a duel so this makes it difficult for him to develop and help his team win, the only way that Haaland can possibly do next season is to keep his distance from the opposing defender when he has the ball so that he can fire a shot towards the goal.