Basically, I don't think we are going to learn anything from this island model because we can make it as arbitrary as we choose.
I agree with the arbitrary part.
However misusing words is common in this forum. I don't think anyone can disagree with that. And we can not have fruitful discussions without an adherence to the definition of words.
The island model is a simple conceptualization of possible human interactions. Use the island model to reach a point of understanding over words and ideas. We can use the island model to clearly distinguish our differences over certain types of human behavior.
The island model can then be used to justify why one outcome is favorable over another in terms of human behavior.
Of course the island model will never be able to capture every aspect of human behavior, but what model can? At the moment half the content on this forum is disputes over what words mean. If we can't come to an agreement over words then what is the point in using words?
A few things on the island.
An island obviously represents an isolated community. It shows how one outcome in one community can dramatically effect the welfare of others.
The island model should be used to separate ideas into two different levels. The micro level of the individual and the surrounding the community and the small community interacting on the macro-level. By distinguishing between the levels it is simpler to build a statement and show the reasoning behind the statement. Disagreement can be shown in terms of levels. By distinguishing the two levels it can be shown the outcome of one level upon the other.
If statements are going to be expressed in an imperative mood then the island model should easily show correctness. Otherwise it is likely the statement is false.
The island removes the idea of government and reduces coercive force to minimums. I have shown how authority arises from an innocent situation. We disagree on is the likely-hood of such a situation and its relevance. What we are really disagreeing on is a fundamental aspect of human nature, how a small component of the individual shapes the entire community. And this is good IMO. This shows where we disagree, and can walk away. Also historical literature can be used to justify one outcome over another.
The island is an important abstraction until there is better agreement over word definitions. Consequently I think it should be refined and used more.