USSEP Changes Reverted and Tweaked

Reverts and/or tweaks over a thousand poorly implemented or arbitrary changes the USSEP makes. This includes properly fixing bugs, reverting erroneous or unnecessary changes, and restoring vanilla intent where a bug is not actually present. Exploits are not restored. \
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This is meant to serve as a vanilla-faithful mod but still keeps any appropriate bug fixes and also includes some extra relevant fixes not included in USSEP.\
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Backported for 1.5.97\
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UPDATED for Unofficial Skyrim Special Edition 4.3.4a Backport