The basic things I understand are (and please anyone correct me if I'm wrong):

Turn Radius varies with true airspeed and load factor.

Turn Rate varies with true airspeed and load factor.

A coordinated turn has no sideforce (well realistically almost zero).

A rudder in a coordinated turn is needed (mainly) to overcome yaw rate dampening, which acts in opposition to the established yaw rate (i.e. positive yaw rate for a coordinated turn to the right).

An aircraft can exhibit a yaw rate with zero sideslip.

Yaw vs. Sideslip:

Sideslip is described as the angle generated by the relative wind not being aligned with the geometric longitudinal axis of the aircraft.

Yaw (the angle of yaw) is defined as the angular displacement of the airplane's geometric longitudinal axis in the horizontal plane from some arbitrary direction taken as zero at some instant of time. Yaw can also be used to describe rates and moments.