Why does my printer create notches on the Y surface?
I see two problems with your printer: your filament seems to overheat in some areas, and you overextrude a little. My suspicion is, that your heating behavior is not well tuned and it overshoots the target temperature, leading to an overcooked filament, then the temperature drops below the temperature you need, leading to a wavy pattern and brown lines.
fixing
I suggest running a PID-tune cycle to get better heating behavior and then recalibrating the printer's extruder.