Re: Iron Man needs to stop fighting evil Iron Men
If they could manage Whiplash, then I see no reason for characters like Blizzard or the Melter. However, I would've liked Iron Man to fight all three in Iron Man 2 a la Casino Fatale/ Pieces of Hate. That would've been more fitting if Justin Hammer was in the movie as well.
There are also other characters like the Unicorn or as someone said, Living Laser.