Here's an idea... For those people familiar with looping on a Boomerang III or Roland RC-50, it might really help them immediately feel at home with Loopy if there was a default setup option to assign MIDI control actions with an external controller that would emulate the foot buttons they are used to.
For example, if button 1 on a Boomerang III or RC-50 has one function when you tap it and another when you press and hold it, then it'd be nice if you could go into Loopy and say "map button 1 off my external controller to do the functions of the Rang III"....etc.
That way out get instant satisfaction and gratification with Loopy from seasoned loopers. And if Loopy is not able to match those functions, then there's your list if features to be enhanced to be added to our "to be developed" list ;-)