The Audit Logs Overview Excel output could be flattened out so that instead of showing the report in an record and details format (one record takes 15 rows).
You just repeat data in the columns and one log record (by date/time) would just take one line with many more columns. I realize that this would increase the size of the output significantly but it is easier to use.
Excel export for audit log reports will be improved and optimized in Q1 2020.