Answering my own question, a list of theories I have yet to study that may yield significant insight:
Theory of Heavy-Tailed Self-Regularization (https://weightwatcher.ai/)
Singular learning theory
Neural tangent kernels et. al. (deep learning theory book)
Information theory of deep learning
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Less Wrong (text)
Less Wrong (link)
Answering my own question, a list of theories I have yet to study that may yield significant insight:
Theory of Heavy-Tailed Self-Regularization (https://weightwatcher.ai/)
Singular learning theory
Neural tangent kernels et. al. (deep learning theory book)
Information theory of deep learning