My quad is also less stable in Position mode, but I can reduce the oscillations to pretty much zero by changing Position Hold Gains in Parameters window in QGC: MPC_XY_VEL_P, MPC_XY_VEL_I, MPC_XY_VEL_D.
Reducing the gains makes my quad stable in Position Hold, but it still wobbles if I touch RC transmitter stick. Probably because of large deadband in Pos Hold mode, but not sure.
I have some comments and values here (last post):
