You have to have Character but do you also need to have Personality?
Temperament, charm, likeability – these are the words associated with Personality as distinct from Character which is knowing the difference between right and wrong.
Personality is not being “Jack the Lad” – ever ready with a quip or a retort or a challenge. A personality does not mean you need to be lively and make yourself the centre of attention. You are an arbitrator – not an entertainer.
You do need to be in control – at the end of the day you have the power of decision but do not confuse that with the right manner to enable you to preside over the proceedings and give the parties confidence that you know what you are doing.
You can achieve this by being quiet and not noisy – by using few words rather than more – by speaking plainly and not flamboyantly.
All of this is important. You have to set the tone for the way matters are to proceed. Of course you do not want to be dull, monosyllabic, or inaudible. You do need to sell yourself so that the parties can have confidence that you are in charge but get the balance right between being too jokey and too miserable.