I don't view it as being anything quite like the ending of M9. To me, everything after the high strings make their huge, ascending glissando, is pretty much the end of the piece. In short, it doesn't bother me so much. . . . . . And again, if it were me in charge, I would end it with offstage cowbells chiming away for 7 to 10 seconds - tons of them, really far off, and possibly discretely piped through the hall's sound system to obtain a more surround effect.