Do not keep retrimming. Set the trim for a given power speed. Doing it even in turbulence becomes second nature.
It maybe worth watching what happens when you have the aircraft on autopilot with alt hold in moving air.
Watch the VSI and the ASI ON on autopilot. You will notice as you hit rising air the VSI will indicate a slight climb. The aircraft will compensate by trying to hold altitude by pitch forward. As it does so the speed increases on the ASI which further increases the desire for the aircraft to climb.
Watch what happens in sinking air. The VSI indicates that sink! the auto tries to hold altitude with the result that the aircraft pitches up and the airspeed declines. ETC ETC ETC.
You could not possibly be trimming for every movement in the air flying manually so trim it for still air and then command the aircraft to hold altitude with small amounts of pressure on the control column.
Scan out of the aircraft but also watch for trends on the VSI the altimeter and the ASI.
If the VSI starts to show a trend followed by a movement up on the Altimeter command the aircraft back onto the altitude and hold it there. It is a matter of slight pressure on the column if you have the aircraft trimmed correctly for still air.
Pace