Add some intelligence about column widths. For example in this query:
You can reduce the width of the columns and fit more in in the view.
add the ability to reduce font size, and padding so that you can fit more columns selectively.
Add the ability to automatically turn a * into columns. It would be cool to double click on a star and it adds all the column names, or have a popup where you can then highlight and select the column names.
You could add option to flip so instead of being left,right panes you could do top, bottom
Add the option to hide the query editor just to explore the data table, similar to going into explore without the columns on the left to build the viz
You can reduce the width of the columns and fit more in in the view.