Small parts print very bad and undefined. Lower temperature. Print slower. Print more objects at the same time to give more time to cool.

Large amount of ripples around corners. This is always present in prints, but when it is disturbingly large the issue is normally that something is loose. Check belt tension and also check if the heated bed is properly fixed onto the y-axis rail. Try slowing down print-speed.

Prints are skewed. Make sure belt tension is properly, also make sure pulley's are properly fixed onto their motor-axis.

Under extrusion. Make sure the filament is not slipping over the extruder wheel and also make sure the hot-end is not clogged.

Object curved away from surface. Check this article...