The game doesn't seem to use up all my PC's power

I’m running the game on i7-8750H, 2070 mobile with a 2k 165Hz monitor. I’m able to get beautiful 60fps at 1080p balanced settings now at some locations, but sometimes the frame rate drops to way lower, especially in Sacrement. However when I checked the system hardware load none of the main components are working under full load. The CPU and GPU are at 60%-70% ish and both VRAM and RAM at 70%ish as well. It surely wasn’t because of fps lock since the fps is significantly lower than that. Was that caused by something in settings or just room for optimization and improvement?

BTW, currently 11hrs in and absolutely love every aspect of the game. Even the ones lots of people dislike about like item durability or city upgrade time. Good work devs!