This is all you need for mode change instead of doing all the if and elseif statements:

on @*:INPUT:#: { 
  if ($regex($1,/^((?:\+)|(?:\-))([a-zA-Z]+)$)) { 
    mode # $+($regml(1),$regml(2)) 
  } 
}

Note: I didn't include the chanop and ban but they can be added this way.