Google-sheets – Auto Sort Sheet on second entry

Simple triggers like onOpen and onEdit have restrictions.

In contrary of onOpen and onEdit that are reserved words onChange it's not, but its commonly used to name an installable trigger to be called by the spreadsheet change event. In the same way it's possible to set functions to be called ty the the spreadsheet open and change events which not have the restrictions of simple triggers.

We could create simple triggers manually or programmatically.

For further details please read Triggers and Events Guide.

I don't think rowHeight can help you here, because it refers to the entire row, not to any particular cell in it. Sorting each column by RowHeight would just rearrange the rows without making your spreadsheet more compact.

Here is the script that sorts each column by the length of cell content, ascending. The first row (headers) is left in place; empty cells are ignored.

function myFunction() {
   var ss = SpreadsheetApp.getActiveSpreadsheet();
   var sheet = ss.getActiveSheet();
   var range = sheet.getDataRange();
   var width = range.getWidth();
   var height = range.getHeight();
   var column, i, j, content;
   for (j = 1; j <= width; j++) {
     column = [];
     for (i = 2; i <= height; i++) {
       content = range.getCell(i,j).getValue();
       if (content) {
         column.push(content);
       }
     }
     column.sort(function (a,b) {return a.length - b.length;});
     for (i = 0; i < column.length; i++) {
       range.getCell(i+2,j).setValue(column[i]);
     }
     for (i = column.length; i < height-1; i++) {
       range.getCell(i+2,j).setValue("");
     }
  }
}

But in practice, this particular sort does not help all that much, because (as you noticed) the longer texts can still match up against shorter texts. Here is another sort, somewhat along the lines of what you mentioned: after sorting, each column is dropped down so that all the longest entries are in the same row. This will typically result in some empty cells at the top.

function myFunction2() {
   var ss = SpreadsheetApp.getActiveSpreadsheet();
   var sheet = ss.getActiveSheet();
   var range = sheet.getDataRange();
   var width = range.getWidth();
   var height = range.getHeight();
   var column, i, j, content;
   for (j = 1; j <= width; j++) {
     column = [];
     for (i = 2; i <= height; i++) {
       content = range.getCell(i,j).getValue();
       if (content) {
         column.push(content);
       }
     }
     column.sort(function (a,b) {return a.length - b.length;});
     for (i = 0; i < column.length; i++) {
       range.getCell(height-column.length+i+1,j).setValue(column[i]);
     }
     for (i = 2; i <= height-column.length; i++) {
       range.getCell(i,j).setValue("");
     }
  }
}