Let me just start out by saying that I'm not frustrated about the cost. Crossing bloodlines of animals has always been a rich man's sport.
What is frustrating is that unless a talent pops with training, you don't know what if your mix has the talent or not for hatching purposes.
Please make it so that at some point (ancient?) you can see all latent talents. Not only would this make hatching possible, but you would have an idea if its worth while going to epic.
Even if it IS a rich person's sport, I don't really like the cost. I enjoy mixing pets, but I'd love it even more if it was cheaper. And I agree with meiser, because you might do all the hard work for nothing. :( :( Sigh...
And another frustration is trying to find someone to hatch a pet with. We need some way to match up with people. Going from realm to realm for hours in the pet hatching area did not work. I ended up buying a house instead.