I find the length field redundant. Two character emotions could be null padded, making three the standard length. This would save a byte for angry and evil. If evil and angry were removed (merged with sneaky and frustrated), emotions could be two bytes. Better yet, a lookup table could be used with a single byte. One other idea, which applies to all cases where 7bit ASCII is packed into 8bit bytes, is to have the eigth bit aroused on the last character