Is great gluten-free extruded pasta possible?
I have never used extruders, but I make a lot of tagliatelle using my pasta roller. I expect extruders to not be as easy to use with gluten free pasta (please correct me if I'm wrong), as the gluten free dough is shorter than normal pasta dough.

The pasta roller doesn't really change the dough too much with gluten free pasta, as you say a big thing is to develop the gluten, so it's mainly to get the correct shape. One thing with gluten free pasta is that the resting period is really important, if it doesn't rest long enough you will end up with a dough that is impossible to work with.