You are merely assuming what you are hoping to argue. If I say that you cannot "be a particle", because there is no such thing, how does your argument still proceed to unification?
But what a mouthful that "probabilistically as appropriate" part is! How does a particle "do something random" when it is "appropriate" to do so? We might be able to unify everything with which we are familiar, like probability concepts, but we will never unify everything there is. Does the thought ever become unified with that which is thinking it?
If we are not capable of unification, then we have no unification. How do we profit scientifically from imagining something exists that we are not capable of demonstrating exists? Like someone using the North star to navigate, we work for unification because that is the proper direction that science is pointed in, not because we think complete unification is attainable.
Except for all the "cracks" that always remain, such as the need to apply boundary conditions to our equations, and the need to be able to design experiments within our technological and intellectual capability.