Us agents are always going to say, look for an agent exactly like us.
I think communication is the most important factor. Find an agent who lets you talk, who listens, who understands you - and who you understand. Probably 90% of all real estate problems stem from mis-communication.
The widest difference between real estate agents isn't in the job that they do, but in their ability to prospect and convert prospects. That's a valuable skill for the real estate agent's family, but maybe not so much for the home seller or home buyer.