Well putI would not use an Andalusion.
In fact I would not use another breed at all. There is enough decent Spanish around to use, and there is no need to go outside the breed. Some have went outside to the Black Minorca, and that is an option. But . . . some have already done it. I do not see a need to do it again.
The word diversity is overused and misunderstood, concerning the genetics of a flock. What you want is a strong ,healthy, viable, uniform flock that represents the breed well. Going outside the breed is a consideration when no accessible strain has the trait(s) that you need and you have become convinced that it is not in your flock to have. Then you play with that on the side and get it right before you commit to it. Otherwise you could make a mess.
I like the Spanish and have been watching who has what. A benefit that we have with the internet. I do not know who all has what completely, but I think there is everything that is needed is there based on what I have seen online.
I have not looked back through the thread to see what you have again, but for now, work with what you have. It will take a generation just to have an idea what you have. You do not just have what you see, you also have what is there that is unseen.
To make sure that your question is answered, you can change anything into anything by going back to one side continually. It is just a very long term commitment, and there would have to be no other good options to make use of.