I have made a few mini twister patterns and it was suggested in the directions to use a small rotary cutter rather than the standard 45mm one we usually use for cutting fabric. It is a good tip. I went out and bought one just for this project and I rarely buy new tools. I am still using my 20 yr old rotary cutter, but the small one has been a good investment for me.
This may be helpful in ending those overly deep cuts from the 45mm blade.
peace