Just to start things rolling, here is a wacky idea for an object:
With these super strong heroes, who does not want to toss some cars around?
There are some object packs for Heroclix that give you indoor and outdoor objects that may be of use or interesting to make into cards. They have lamposts and mailboxes, etc.
By the way, the car is a 1/43 scale vehicle that takes up two hex spaces.
I have a few of them in different styles (SUV, etc). You can find them at Toys R Us.