The perfect wood for my Projects

Hello guys.
I am using a 10W Atomstack laser and i already did some tests with 4mm poplar plywood.
its very good for cutting but breaks kinda fast so i dicided to buy birch plywood 4mm.
unfortunately i need 3 times more passes (12-14) and it looks terrible. i rly tried out a lot of diferent settings but still really bad results.

My question is: what wood should I use for this laser engraver? Is poplar plywood really the best, regardless of thickness?
It should be as stable as possible but still efficient.

You guys have any ideas?