Something to think about...
By creating a hybrid, or a cross for that matter... with thayeri or any other kingsnake from Mexico because it looks cool, you are essentially doing your small part in destroying the captive population of those animals available to us here in the US. We can no longer capture and import these snakes from Mexico. What we have now is most likely all that we may have for a very long time.
If you continue to educate yourself enough about this, you will discover that not everyone behind you will honestly represent the offspring from hybrid breeding programs as hybrids; either by simply not caring enough, or just plain not knowing any better. Eventually, no matter how hard you try, a percentage of your hybrid/cross breeding program offspring will filter out into the captive population represented as one or the other, when they are actually both. Someone just beginning like yourself may end up with these crosses or hybrids thinking they are pure, so naturally they will label all offspring they produce as pure, one or the other. I'm sure you can easily see how over time if too many breeders continue to do this, it could really begin to spoil the pot much more than it already has. Matter of fact... unless you are really careful and are willing to pay a good price and buy from a reputable breeder who works hard to maintain pure lines, you just may go out and buy yourself a couple of mixed animals to begin with.
Now, let's pretend and say you already know all of this and don't care that much, you just want to produce cool and unusual looking snakes to sell. Who are you going to sell them to... and how many people concerned about this issue are going to want to have anything to do with your snakes? The majority will know something is up just by looking. It is possible in this scenario that if you decide to, you will have a hard time establishing yourself and building a good reputation.
Worst case scenario is, and I say scenario meaning I don't absolutely positively feel it is definitely going to happen, if the pure lines of these snakes at some point disappear from captivity, that's pretty much going to be it. Continue studying the animals and then make your decision as to what you feel is the best thing to do.
Mike