What do you regard as the most important differences between arbitration and litigation in court?

ENFORCABLITY, EFFICIENCY, FLEXIBILITY, ECONOMY.

The great advantage to parties in electing to settle commercial disputes via arbitration, as opposed to litigation, are as follows:

First, the parties are permitted to select the decision maker hearing their dispute, which allows them the freedom to select (a) decision maker(s) who may have certain desirable characteristics, such as subject matter expertise, that might be necessary to fully understand the nuances of the dispute in question, including industry standards and practices.  

Second, in selecting arbitration, the parties are afforded the opportunity to construct and tailor the arbitral procedure to best suit the dispute and effect procedural time-saving and monetary economies.

Third, the parties can agree to add on procedures like mediation efforts and/or appellate review by a panel of appellate arbitrators.

What are the most important qualities for a successful arbitrator to have?

Good practical sense, decisiveness, strong listening skills, strong verbal and writing skills, and superior sense of fairness and neutrality; ability to detect unconscious bias and prejudices.

What are the best ways to achieve efficiency in arbitration consistent with fairness to all parties?

First, listen more, speak less.  

Second, be prepared.  Know the case and submitted materials thoroughly.

Third, hold a Kaplan Opening, where any procedural issues and questions of law and fact are raised before the hearings.