I find... Since I have owned and rescued veils, the "mirror" effect is handy. I bred a crowntail to my veil, Meagan, and since she had a very good dorsal and caudal (even, without damage or imperfections) the baby, a female, looks like her. I wish I had a male or that she had a shorter anal fin, because the fin is too long IMO... BUT raising a standard, instead of willy nilly breeding and aiming for a single form would be best. I have had veils with weird squared, wonky, or slanted fins... Then some with spade, rounded, and very strong fin lines. I would breed for "mirror effect" possibly shorter anal fins and not so delicate fins. Maine had wonderful, full fins. Spartan held his fine well. Meagan had decent semmetry. Fiona had a spade tail. Etc
Adding: but be reminded that you would have to breed solely for perfection, cull hard and make zero profit. Veils are too common to breed as is, so it would be a money-munching trial