Acceleration vs stepping mode


I've been trying to build an X,Y router. Using steppers with pinion gears and a DIY rack, this router is meant to be standing ( so Y-axis has to fight against gravity ). But this is not working with rack & pinion, it's losing grip so i'm looking for trapezium leadscrews.

Problem; with the current motor speed its going to take ages to move across one meter using leadscrews. I'm trying to speed up the steppers, i'm using accelstepper to let it accelarate to a decent speed. I've tried different microstepping modes; Eights, quarters and full-stepping. Eights is slow, quarters are ok. But when i try full steps the motor stalls in the acceleration proces (even on low speeds), why is this? (should i try increasing the current and is this also a solutuion for getting more torque on higher speeds?)

I'm using a Easystepper driver v4.4 and a 39BYG013-7 stepper (rated current 0.4A). Highest result was 10000 steps per second (Quarter step)