Building a midi controller

Hi everyone,

I'm new to the arduino world and I like to get some advices. I'd like to build a midi controller with a lot of analogs inputs (potentiometers, switch, fader etc.)

Is the due will works with these inputs as it is a 3,3v ? it's 3x a mega, maybe it worths the price ?

Should I take a uno with a mux shield like this one or a mega ? I see on the picture that the mux as connectors at its back. If I take the mega, does the connectors will touch them each other ?

Are they any advantage of buying this : over making this ?

Can I use the Sparkfun midi shield with the mux shield ?

Will it be hard to switch from the arduino to another dedicated microchip later ?

Thank !