No it's not a reason why aircrafts do turn when banked.
But yes, discrepancy between center of lift and center of mass produces a torque.
Ideally, center of lift= center of mass. If this is not the case you need to trim your controll surfaces to account for the torque (unless it becomes too extreme in which case the aircraft becomes uncontrollable/unstable)
That's why rules/guidelines exist for all (military and commercial) aircraft how much mass imbalance you are allowed to have, in which order you are allowed to fire your weapon, and in which order you have to deplete your different fuel tank cells and so on.

As we dont have trim in A3 it should be avoided to have center of lift outside center of mass/ vice versa.

Here is the proper explanation why an aircraft turns.
http://forums.bistudio.com/showthread.php?167067-Fixed-Wing-Flight-Model-(dev-branch)&p=2793625&viewfull=1#post2793625

the banking turn of an aircraft cant be explained with centrifugal force. It's an aerodynamical effect that causes torque and therefore produces centrifugal force. Proof is the simple fact that you cant make a banking turn with an aircraft in vacuum, even if you had "lift" and gravitational force.

Torque that aligns plane with descending speed is physically wrong/ incomplete. It needs to work for all coordinates and speeds.

See here for how it could be done:
http://forums.bistudio.com/showthread.php?167067-Fixed-Wing-Flight-Model-(dev-branch)&p=2793937&viewfull=1#post2793937

IMPORTANT

The forces and accelerations are not calculated correctly. Something is broken with it. See here for the REAL explanation, tests AND A WAY TO FIX IT:

http://forums.bistudio.com/showthread.php?167067-Fixed-Wing-Flight-Model-(dev-branch)&p=2793625&viewfull=1#post2793625

http://forums.bistudio.com/showthread.php?167067-Fixed-Wing-Flight-Model-(dev-branch)&p=2793858&viewfull=1#post2793858

http://forums.bistudio.com/showthread.php?167067-Fixed-Wing-Flight-Model-(dev-branch)&p=2793937&viewfull=1#post2793937

Despite a constant gravity force when 90° banked, the aircraft has a fixed speed in that direction, doesn't accelerate. I think this is the main source for many problems that people experience.

just fly up high into the clouds with an airplane and turn your view... it's horrible and you get easily confused where up and down is if you dont look at aircraft instruments.

physx simulation only allows 20wheels at max. Tank wheel count is already high (Kuma= 18 wheels). There is no workaround possible with extra wheels.

related to http://feedback.arma3.com/view.php?id=19183
and http://feedback.arma3.com/view.php?id=20078

Tank tracks dont exist, they are just visual. Nvidia PhysX model is based on wheels, therefore it will behave like wheels. PhysX doesnt allow complete and very realistic track simulation.
I don't know of any other game that has real tracksimulation, and i doubt we will see one soon because realworld Trackphysics are complex and calculationintensive.

Real track physics are very likely out of scope for Arma /it's unrealistic to expect it. As long as 0-speed torque is fixed (/ the clutch system is fixed) and controlls are repaired it will be much better.

big issue... you can barely see anything when shooting because the gun dust looks solid