Current IDLE indicates the SyntaxError position given by Python by highlighting the character, as in the editor.  No more caret.  End of problem.

There is no fixed-width Unicode font.  I revised the font sample in part to let people see which alphabets fixed in a particular font face.  Courier likely is best for this: Ascii, Latin1, IPA, Greek, Cyrillic, Hebrow, and Arabic all have the same fixed pitch, but this makes for some badly scruntched characters.

I emailed Pratik about the userid issue and the solution (upgrade).