I'm planning to install two piezo pickups to my acoustic guitar, what could i add also ? like a volume swicth, a tone switch is it possible or some equalizer like in the electroacoustic guitars?
Why 2 piezos?
You need to put the piezo underneath the saddle, which can mean drilling through the soundboard.
You also need a preamp with the piezo, which can be external or internal (Internal will require modding the guitar), which will have the volume and tone/EQ controls.