Lowering CSG model's part count

Hello :wave:, so I build CSG vehicles on studio based on the irl counterparts for roleplaying games. Now I never really cared about the amount of parts I use while making these cars but recently it hit me. Since I’m trying to make a game myself I realized that I needed to lower part counts.

However I also want to maintain the smooth asthetic of the car(s). So it begs the question, what can I use to lower the part count of said cars.

I’d appreciate any feedback or help