I agree with you. I have tried to stagger the scarphs as much as possible and it does not always work. I have to take in account the bluff bow and the steep curve in the stern area. Furthermore, the first couple of strakes close to the keel was a practice. It will be painted and in general no one will see this.
From the bilge and up I will do a better job of staggering the scarphs.
Presently I created planks of 20cm long, this includes the scarphs on each end. Dry-fit and glue them on the hull.
I can cheat a bit by glueing a 45cm plank on the hull and then at every 15 to 20cm create a scarph joint with the scarph cutter. I have done this to see the difference between that and having the planks pre-cut.
It makes for a nicer cut and gives it a tight fit at the joints.
Marcus