I won't say anything about isildur since you can't see him, but I really love your metalwork on sauron. especially the tarnished bronze plates. I am inclined to agree however, that the base needs some work. It's something I need to work on too, but I have to say, as it stands it looks kind of like the epic scene is being acted out on my front lawn.
These minis look excellent. I won't judge more of the king who's showing mostly his back. Let's just say that he seems good. About Sauron, he's impressive. There seems to be differents highlights: some more green, some more black. I don't know if it is because of the picture but it is nice. Maybe he's a bit dark but man! He's the Dark Lord, not Pikachu!
Actually the thing you could really increase seems to be the bases. These two guys are begging so much for a scene! Of course it is much more work, but I think it would be of the greatest effect.