Integer sort is ok, but could you replace the leading zeroes with blanks, and right justify. I've not tested floats because I don't have any.
I am not interested in seeing the book path (I can hit ctrl/d if I need to know), is/could there some way of suppressing its display, e.g. a check box as for series, ratings etc.
And could the current column name be displayed in the status line, or the current cell/column be displayed in a darker/lighter shade - or both
BR