In the context of structural dynamics, recent works by the authors showed that microperforations can be used to mitigate vibration. Microperforated plates (MPPs) have been shown to exhibit substantial added damping stemming from fluid-structure interactions and visco-thermal effect mechanisms in the boundary layers of the perforations during relative motion between the solid and the fluid contained in the perforations. The added damping reaches a maximum for a characteristic frequency, depending only on the perforation diameter. Choosing the perforation diameter so that the characteristic frequency coincides with the natural frequency of the plate reduces the mode contribution of the plate. However, the studied MPPs had a single set of perforations homogeneously distributed over the structure. It is proposed in this work to broaden the frequency band and maximize the added damping using MPPs with multi-sized perforation diameters and optimized spatial distribution of perforations. As an extension of the previous vibratory model by the author, the dynamics of MPPs with multi-sized perforation based on a homogenization model is established. In addition, the effect of the spacial distribution of perforations on the additional damping is captured by including a spatially dependent perforation ratio in the model. Experimental measurements on MPPs validate the proposed analytical models. The results show that: (i) MPPs with multiple size perforations exhibit a broader effective damping frequency band; (ii) the added damping enhances when the perforations are distributed in the area of the antinodes of the considered mode. Thus, by coupling the two effects, it is possible to achieve MPPs that effectively reduce the vibratory responses on several modes.