The characteristics of the output capacitor affect the stability of the regulation system. MPM3630 can be optimized for a wide range of capacitance (ceramic caps, tantalum, etc.) and ESR values. In the datasheet, from 1.5A to 3A, Vin = 12V, and Vout = 3.3V, the pk-pk transient ripple is about 200mV using 2 x 22uF ceramic caps at the output.
For a slew rate of 2.5A from 0A to almost full load, if you'd want a pk-pk transient ripple of about 200mV or less as in the datasheet, for best results, you could use 2 x 47uF in a 1206 package because 0805 package would be a bit marginal in terms of achieving that transient spec. Hope this helps!