Build a MIDI-Controller

Hey Guys!

My and a friend want to start our first project with an arduino uni: A midi-controller to send midi inputs to a Computer (DAW-program) over digital and analog inputs (button matrix, twist/slide potentiometers, joystick and proximity sensor).

I don't know if my selected parts fit together, can you maybe take a look at it? I want to order through mouser, so you can suggest me products there, if you may have a better idea for a part.

Slidepotentiometer
http://www.mouser.de/ProductDetail/Bourns/PTA1543-2010DPB103/?qs=sGAEpiMZZMtC25l1F4XBU6KQRTmUDfzVWK25cQp5oD4%3D

Twistpotentiometers:
http://www.mouser.de/ProductDetail/BI-Technologies-TT-Electronics/P120PK-Y25BR10K/?qs=sGAEpiMZZMtC25l1F4XBU7XpbFdDDzhr3lOUxKiBOhk%3D

IR Proximity Sensor:
http://www.mouser.de/ProductDetail/Broadcom-Avago/HSDL-9100-024/?qs=sGAEpiMZZMs3uAJYYmvlK5NGg1IRy8rgmhGFGmsJ9oo%3D

Joystick:
http://www.mouser.de/ProductDetail/Adafruit/444/?qs=sGAEpiMZZMsMyYRRhGMFNrRsV%2btmI%2FmAFDonM2fQq6U%3D

Selectswitch
http://www.mouser.com/ProductDetail/Grayhill/50J2080-1/?qs=sGAEpiMZZMtFyPk3yBMYYDdos7hL8SgoZ3oK5L79oII%3D

Push button:
http://www.mouser.com/ProductDetail/Apem/MJTP1234/?qs=sGAEpiMZZMtFyPk3yBMYYM4hYjBerRHjTttXOA8BmmU%3D

Push button caps (do they fit? o.O):
http://www.mouser.com/ProductDetail/Grayhill/95CAP-104/?qs=sGAEpiMZZMtFyPk3yBMYYDdos7hL8SgoX6WVQsy5VfU%3D

Do you have any other ideas? I thought of a TFT Panel, but there are so many parts on mouser.com, I have no idea which one to choose and to use with seriel connection (because I need the pins). Do you have any advices for around 10-20 Dollars/Euros?

Greets
Chris