I would include Lovestreet at the beginning and Bad Blood after Milligan's run because IMO Bad Blood is the true ending to the Constantine saga.
I've got my run bound all the way thru the end of Azz.
It's a little different as I included the second short Ennis run along with Ellis since they were collected that way in tpb.
I'll probably go back and do a "zero" volume and collect all the mini-series and Pandemonium which I completely forgot about.
So far the only one I included was the two-issue one by Jenkins.
Also, I want to find a spot for HB's appearance in Shade. I think it was a four-issue stint.