the best way to tell male from female is to watch the spawn and take a look at the ovipositor(breeding tube). the females tube is short and thick.. the males is thin and longer.
males are not always bigger than females. generally I would agree with this(males larger than females).
however, i have seen females that are very large.. bigger than the males.
I have a large female in one pair..she is almost as large as the male...and larger than my other breeding male. I have three confirmed pairs.(I think the size has more to do with the lineage)
I find that the wild fish (in my case) grow faster as they are more aggressive at feeding.
.
Another way that I've noticed is that the females, as with humans, are a lot meaner and a heck of a lot more dangerous.
I lost a beautiful black male that was almost the size of my palm. He must've eaten the eggs and the female, that was half his size, took a chunk out of his forehead that looked like someone had run a 3/16" router bit across his face. When I reached in the tank to remove the recently departed she went after me. Freaked me out. Never thought of angels as being the least bit aggressive, at least not to that level.
I'm pretty new to the hobby but I tend to agree that the further from nature the hybrid gets, the less aggressive they feed and the slower they grow out compared to the wild caught. I have some pearls and half blacks that are standards and they'll practically leave the tank to get to the food where as the super veil zebras seem like they could care less.