For the whole series? Some here and there.
DMC1-
Phantom, Griffon, and Nightmare. These bosses made an impact and by god did they make an entrance. Their scale wasn't the only thing, it was their impressive stature (yes, that is not the same as scale) and imposing presence.
Deaths and Sins, Shadow, and Nobodies. Pretty much anything that laughed really added to the personality of the game and the opponents and gave the demons a twisted psychology as well as some fairly hellish imagery.
DMC2-
Despair Embodied. There used to be this guy around here called moseslmpg with whom I argued a lot back at IGN. He released his research on the achemiec ritual that took place in DMC2 and the hermaphrodite creature it revolved around which had an angelic appearance. That was the Despair Embodied, and if the thing wasn't cool looking enough it came with this gnarly backstory.
DMC3-
Cerberus and Vergil. Really the only ones I found that interesting. Everything else ranges from good enough to unimpressive.
DMC4-
Berial. All the other bosses are down right stupid looking. A plant snake and a frozen frog... I'm not saying that those concepts wouldn't work, I'm just saying that here they were crap.
DmC-
Drekavac, Stygian Elite, and Wisps. Bosses are not interesting looking to me and the general enemies are not that fascinating. The Drekavac is, on the other hand, a more imposing figure that actually looks of personality. The Stygian are lame and don't feel threatening but the Elite have a more menacing look. It's the teeth. The Wisp, now there is something that looks like it came from nightmares. Generic as it looks, like your standard scarecrow/crow motif, it still has enough freight to stand on it's own as a creature of dark origins. I almost added the Imprisoner but honestly I think it looks more sci fi than horror.
Honestly, there are few creatures in DMC that I find that compelling. There are very few that scream 'demon' as opposed to Grim Reaper (not a demon) or evil anima/object/creature (Not demons ether). There are just few instances where if I wasn't familiar with the games I would go 'yeah, that thing looks like it came from hell' which is something I think every time I play Silent Hill and look at their creature designs.