I will let you know, the main reason why you hear so much "Don't breed this to this and don't breed this to that" is because there are certain pre-conceived notions of what a certain morph should look like.

Snakes that come the closest to that ideal will always sell faster and for more money.

While snakes that don't come close to the ideal, or are on the other side of the country from the ideal are in general much harder to sell and will not fetch the higher prices of snakes that do meet the ideal.

There will always be variation. Both in snakes of a certain morph, and in what people like in a specific morph. However, years of experience in the field and thousands of reptile shows attended you pick out trends, you can't help it. A bright yellow bumblebee with little or no flecking and a crisp, clean pattern will always sell faster and for more money than a dingy greyish/yellow bumblebee with tons of flecks all over the body and a muddy pattern. Even if some people prefer the greyish bee, more people want the super bright yellow. By breeding to cater to the market, you sell your snakes easier and make actually make food costs some seasons. Sure you can breed only for yourself, I know people who do. If you don't care how long it takes to sell a baby, or that you must ask $100 less for your snake than a market standard snake sells for, then by all means breed for yourself. No one can tell you if you should or shouldn't breed to market standards, that is a choice you must make. But be aware of the choice you make and how it will affect you.

I see dark orange and orange/yellow pastel babies at every show for $50, and usually they appear from one show to the next, because they are hard to sell when they are not yellow. Sure there will always be people who buy it just because it's cheap, but by and large, they don't sell easily.
Robyn, an Admin here, has a Pastel male named Winston. He produces exceptional babies, she sells them for quite a bit more than $50, and she always sells out. Most of the time she has a waiting list in fact. And why? Because her babies are worth it. They come from exceptional market standard parents, and go above and beyond most anything you'll see in the market. People know this, and they don't hesitate to acquire a snake that will add so much to their breeding stock.

I am not trying to tell you do this or don't so that. Just be informed and make the choices that work for you. That's all any of us can do, really.

Gale