Cynical
MOE
Well, I'd say efficiency is a characteristic. "Characteristic" in and of itself is rather vague though. If you speak of characterization or personality traits, then I'd say effectiveness doesn't really do the job. It is a characteristic in the sense that it helps define a character. For me however, it's not a very "effective" description. Potency might be better. Of course, it's subjective.
it is equitable
Biometrics
Personal characteristics is a uncommon trait a person has that makes them distinct from others. This characteristic is not always recognizable.
Please restate your question. We have to know in what area you want her effectiveness. For example, do you want to know her effectiveness in politics, economics, personal relationships, etc?
Vocabulary and articulation are two personal characteristics that will often enhance the effectiveness and ability to communicate well with others. Communication is an important factor in most everything involved in daily life.
Personal characteristic.
intense personal emotion
Biometrics
much benifit to all