This is my way of doing it using regex (which saves you about 600+ bytes):

on !*:rawmode:#:{
  if ($regex($1,/([+-])(q|a|o|h|v)/)) && ($2 == $me) {
    var %m = $replace($regml(2),q,~,a,&,o,@,h,%,v,+)
    msg # $iif($pos($regml(1),+,1),Thanks for the %m,Don't take my %m) $nick
  }
}

You don't really need the halt, and it's better you use the case sensitive version > === or > isincs because your script will trigger if the mode is either upper or lowercase. My example of regex is by design case sensitive unless the /i modifier is specified. The exclamation mark by the event is not to be triggered by the client running the code.