Incremental Nonlinear Dynamic Inversion (INDI) has gained popularity in various aerospace control applications, as it reduces reliance on accurate models and improves disturbance rejection. Recently, the incremental control approach has been combined with classical proportional-integral (PI) control to increase robustness, avoid hidden coupling terms, and enable fast gain scheduling, in a manner similar to the differential PI (DPI) controller. This paper extends the incremental DPI (iDPI) concept to a model-following structure for MIMO systems in the context of fixed-wing flight control. It compares a coupled and a simplified decoupled physical reference model as well as different error controller structures. The approach is evaluated using a high-fidelity six-degree-of-freedom (6-DoF) simulation model of a commercial aircraft, including several practical adaptations to support real-world implementation. The results highlight the suitability of the proposed iDPI framework in achieving robust, implementable flight controllers.