The macro will always “waste” a GCD to refresh Serpent Sting after five Kill Commands and cast Raptor Strike with ~3 Tip of the Spear stacks. If you want ti to be mostly automated, there isn’t a good way to change this.
That being said, with the last update I made a week ago, it comes really close to the DPS numbers I simmed (depending on procs ofc), not only on dummies, but also in Raids and Dungeons. At least for me.
The only thing you could try is changing the value of the pause block to a higher number. That would mean fewer Raptor Strikes and more Kill Commands, but I guess you would lose DPS by doing that. But give it try.