This is a thought I have had since I was very young.
One possible way for existence to appear out of nothing, or at least out of minimal necessity, is for it to be the most coherent of all possible branches or rearrangements: the single materialized branch that will never “get destroyed” or fail to fulfill the final goal, if there is one. Order or mathematical structure and elegance might be the goal or part of the goal.
All possibilities exist as timeless candidates. For example, there is a possible world in which everything explodes in the next second, but it never materializes because everything ends, or will eventually end, under those circumstances. Or it might fail to fulfill the final goal, such as complete order. The everyday concept of time might not properly apply in this theory; regular tenses of everyday verbs might not make sense because a future potential state might affect the present unfolding.
This echoes the branches of the many-worlds interpretation of quantum mechanics, but there every branch is real; here only one survives. It might also share similarities with the “best of all possible worlds” idea of Leibniz.
Still, it doesn’t account for the existence of the possibilities themselves. Why should the possibilities themselves exist at all?