It's clear that currently it's not possible to use dsp part and the speakers part of amplifi seperately. You can easely put any stompbox before amplifi but you can not use anything between or after amplifi while using it's speakers, except you may use headphones out and might use that signal to feed and stomps and monitor it through another speaker system.
So, if there is not any resteiction by hardware, it would be a practical solution to give an option to send the signal from amplifi's dsp to line-out without monitoring that signal through amplifi's speakers. So that amplifi only monitors signal from aux-in. That way, we can use loopers and other effects, probably using something between for different impedance issue.
http://line6.ideascale.com/a/dtd/4CM-for-Amplifi/637650-23508