Brain Jr. DIY Bass Pedals - buttons to use?

Hello!

I'm planning to use a Brain Jr. to make USB Midi pedals to control a bass synth while playing guitar! My aim is 13 playable notes, 3 generic midi on/off switches, and hopefully two expression pedals using analog controls?

I must admit I have little electronics knowledge and I am mainly interested in the end goal, but certainly don't mind getting my hands dirty. Overall I am hoping for a construction that is easy to make, cheap, and durable.

any suggestions what kind of buttons should I use? I will be mashing them with my feet so arcade buttons seem a bit fragile. However standard stompbox switches seem a bit clunky for playing notes on?

Here are some of the buttons that are available cheap shipped here (Australia):

1pcs 9-pin 3PDT Guitar Effects Pedal Box Stomp Foot Metal Switch True Bypass New (doesn't really look like what I need but somehow is the cheapest!)

1pcs Momentary OFF-(ON) N/O GUITAR EFFECT PEDAL STOMP/FOOT SWITCH 3V-9V-12V-36V (these are probably most appropriate?)

Transparent Acrylic Tattoo Machine Footswitch Power Supply Foot Pedal Controller (this pedal looks pretty flimsy..)

2013 New Stainless Steel Tattoo Footswitch Foot Pedal Switch+Plug Cord Supply (in fact both of these pre-made pedals are probably crazy ideas?)

In terms of the case itself, I was thinking something pretty simple like this diy board (made using a different controller!) which looks like just a piece of metal and some 2x4's.

I think this is quite nice but is a commercial product. I've also seen lots of people using organ pedals to make their own midi taurus things, but I can't find a cheap set of organ pedals.

How about the expression pedal?

Any ideas or suggestions would be greatly appreciated! Thanks!