Batch row deletions across non-consecutive rows

I'm working on a script to archive (copy and delete) rows from a spreadsheet.

To do this I go through every row in the worksheet to see if it's completed.

I can batch the first copy process by gathering up all the rows and writing the range of values all at the end.

However, when it comes time to delete the rows, I still have to loop through and call sheet.deleteRow() once for each row. I can't use sheet.deleteRows() because the rows are not consecutive.

Here's an example of the way I'm trying to use the script:

function archiveRows_(archiveSheet, sheetID) {
  
  // get req values
  var reqSpreadSheet = SpreadsheetApp.openById(sheetID);
  var reqSheet = reqSpreadSheet.getSheetByName("Mstr_Wrkbk");
  var currentValues = reqSheet.getDataRange().getValues();
  
  // container for staged data
  var rowsToArchive = [];
  var rowsToDelete = [];
  
  // check for archivable content
  var currentRows = currentValues.length;
  for (i = 0; i < currentRows - 1; i++) {
    var row = currentValues[i]
    
    // check if we meet the criteria for archival
    if (shouldArchive_(row)) {
      // add row to archive list
      rowsToArchive.push(row);
      rowsToDelete.push(i + 1);
    }
  }
  
  // archive rows if we found some
  var numRows = rowsToArchive.length; if (!numRows) return 0;
  var numCols = rowsToArchive[0].length;

  // add rows to archive sheet
  var nextFreeRow = archiveSheet.getLastRow();
  archiveSheet.insertRows(nextFreeRow + 1, numRows);
  
  // write archive rows
  archiveSheet.getRange(nextFreeRow + 1,1, numRows, numCols).setValues(rowsToArchive);
  
  // Committ Changes
  SpreadsheetApp.flush();
  
  // delete original rows (we have to loop backwards so delete works)
  for (i = rowsToDelete.length - 1; i >= 0; i--) {
    // delete row from master sheet
    var rowNum = rowsToDelete[i];
    reqSheet.deleteRow(rowNum);
  }

  // Committ Changes
  SpreadsheetApp.flush();
  
  return numRows;  
}

It's this part that runs really slowly:

// delete original rows (we have to loop backwards so delete works)
for (i = rowsToDelete.length - 1; i >= 0; i--) {
  // delete row from master sheet
  var rowNum = rowsToDelete[i];
  reqSheet.deleteRow(rowNum);
}

Is there any way to optimize / batch this operation?

There must be some criteria for archiving the row. Can you use the same criteria to sort, then delete all at once (also copy for that matter), and then un-sort?