Sure lets have a look at it. You are stating that you're looking at different builds for different matches. Something we do all the time. Looking for builds to suit our meta's. We have not tested all the possibilities no. No one ever will because the format is never stagnant. But we test against what we have locally or what we Proxy up and then make choices.
We do this as I said above. I do not understand why you are repeating the same statement that more or less says: "Different Meta's need different builds". This is not shocking news to anyone.
There is a CORE deck. A set of cards everyone agrees on. They do not change. Then after those cards you have the option to mix and match the other slots as you need to to suit specific metagames/matchups (Read meta). These are known as flex slots. This is simply the facts. You do not have to like them, hell do whatever you damn well please, but the facts are the facts. Those facts are that this deck, like all others does not have a 60 card core. It has less than 60 cards and people use the remaining slots to personalise the deck to suit them and their situation. Thus Flexible choices to suit local environmental needs.