Even a small cory cat isn't fitting into the tiny mouth of an angel, so no. As far as feeder guppies, if they are fry or tiny, mabye. Angel's have small mouths, it's pretty easy to determine what they can and can not swallow.
In nature neons are one of their food. If you want to feed live food then I suggest you setup a second small tank and raise your own feeder guppies. That way they will be healthy and you can better control the nutrition.
I'll try that. My friend was buying me some feeder guppies anyways... I'll establish another tank and when they have babies, I'll feed the angelfish their fry.
I have hasbrosous cories with my angels (they grow to 2 inches) and the only time my angels bother the cories is when I feed bloodworms. Sometimes the angels get excited and take a bite out of a cory tail, but they have never done any damage.
I agree that guppies would make great food for angelfish! :dance2: