Vector engraving isn’t satisfying

I need someone way smarter than me to explain to my why this happens and how to fix it. For context, I imported an dwx data file into snapmaker luban an (still) want to engrave it onto a wood board as an christmas gift. After the laser finished the lines where pretty different in thickness and blackness depending on their density and the detail, i guess. I cant explain why and how this happens, but I need to fix it until Christmas ;).
I would very much appreciate your help.
Thanks in advance!

Workspeed: 1500 mm/ min
Jogspeed: 1500 mm/ min
Power: 100%
Wood: bamboo
Workstyle: vector engraving