Tyranny Rex
Oooooooooo controversial. I re-read them all recently and "Soft Bodies" is painful to read, I'll grant you, but that is partly down to the art. However, some of those early Dillon stories and a lot of the later ones (especially Deus Ex Machina and The Comeback) are great - my campaign for a Tyranny Rex collection continues 
I would love a Tyranny Rex collection... I didn't even know there was a Comeback (must've been during my thrill hiatus.) Deus Ex Machina in particular was wonderful stuff... Elvis Machines, Termagants, demonic extradimensional seahorses.... oh, yes.
DeM is a real highpoint. The good thing is though, that it isn't like the Indigo Prime stories where you've got to slog through the early ones until Chris Weston gets on board and that weird alchemy happens - getting Steve Dillon on early doors is a big help. Some are variable but the crossover with Indigo Prime is another goo early one and then it builds to DeM. A trade would have good selling points too as Steve Dillon and Mark Buckingham are big name draws for American comics buyers.
And yes there was a comeback:
"The Comeback" (with Steve Yeowell, in 2000 AD #1395-1399, 2004)
It introduced new elements and really laid the groundwork for a big return and then... nothing. A big pity. Lovely full colour Steve Yeowell art too.