Cessna C172SP Skyhawk - the lack of trimmers (Ms FS2002)

I'm wondering - maybe I should turn all these gyro realism off,
as it is rather not important during FS training, not quite
realistically simulated, and not very difficult, I suppose,
to take care of in a real Cessna

Umm. IRL, your instructor will train you to check the directional gyro
with the magnetic compass every 10 minutes or so. In a lot of older
training aircraft, the drift can put you off course pretty quickly.
Also, on the flight test, the examiner will be watching to make sure
you cross check as well. So it's not a bad habit to get into.

As for yaw, yes you'll definitely need to use pedals to adjust for that
especially when taking off with the usual full power. Pulling power
can also cause a yaw in the opposite direction! Airplanes with a
propeller rotating the other way than we're used to in the US (for
example, I believe, some WWII British fighters) will have takeoff yaw
to the right, btw.

Cheers, Kev