Reply to External components via 1/4" jack

I was hanging out around the internet, and I stumbled upon this company that does modular controllers for musicians and museums and things. The idea is you get a midi hub like this: http://www.eowave.com/shop/products.php?prod=918

And then you connect various components with 1/4" TRS cables like this: http://www.eowave.com/shop/products....en&clear=type1 . This seems like an optimal setup for someone like myself, who plays live guitar and sings first and foremost, and has another DJ type guy controlling electronic sounds as support.

So my question is, is there a way build a midifighter with 4x4 arcade buttons on top, with external jacks add two expression pedals (analogue), two ribbon controllers as per the site (analogue), and a footswitch to use like a stomp box (digital?)? The most I've done with electronics is solder some cables together, but this seems pretty simple. I'm wondering mostly if the software is flexable enough to make something like this run smoothly, with components possibly being unplugged and plugged back in live.

Anyways, thanks for any help you guys have, if I'm going to spend money on a project like this, I might as well give it to a solid group like DJTT who has helped me out plenty before.