Cool to see you are not frightened ! This is the most important !
If you take the necessary time to read,understand,ask questions and not give up you can do almost anything =)
I was talking about the MotorFader module you mention and yes you can chain 2 of them to have your 16 tracks . Buy link : http://midiboxshop.bigcartel.com/product/mf_ng-module-board
My advice would be to buy first a STM32F4 core board http://midiboxshop.bigcartel.com/product/core-stm32f4-board and then try to link 1 or 2 MotorFaders modules to play with.
But motorfaders are expensive,be warned .
You can also start with DIN / DOUT modules ( http://midiboxshop.bigcartel.com/product/din-module-board / http://midiboxshop.bigcartel.com/product/dout-module-board ) to play with illuminated buttons. Would be cheaper .
If you want to mess up with PCB design i advice you to go with KiCAD, even if few (none?) designs are available this format. Infos here: http://wiki.midibox.org/doku.php?id=kicad
If any questions feel free to ask
Bests,
JK Edit : @Zam has much knowledge about the field of motorfaders. Maybe he is the most skilled to answer questions related to this.