... I like Urabrask, simply because while, as Red, he's passionate about the Great Work, he also understands freedom... so he has a 'don't screw with me, I won't convert you yet' mentality with the surviving Mirrodin citizens. XD
I love the whole mechanical/flavor idea of the Phyrexians just being griefers, like all the spells that are [a fairly common effect in that color] + [opponent loses 1 life], like Psychic Barrier, Vapor Snag, Geth's Edict, etc. not to mention the lopsided Praetor effects.
I love it. Especially the first three. Vorinclex indeed blends into the background a bit too much, as does Jin-Gitaxias, though for him that's entirely in-character. I do wish we could see a bit more of Elesh and Urabrask, but hey, it's still a pretty nice job. You really caught the essence of these characters.