Considering the low price of an A4988 module I can't see the point of a DIY version.The OP's circuit has no current sensing resistors and they are an essential part of a stepper motor driver.Just had a thought ... maybe the OP's PCB is intended to take a Pololu A4988 module and make it easier to connect to?...R
Are the PCB traces for motor power capable of carrying the current?...R
Motor current is 1.5A
Can your PCB traces comfortably carry that much current?...R
I don`t know, can i test it or something?