I think it might be easier to list 10 things a good road tech should -never- do, sort of a 10 commandments for road service techs.
I am SOOO tempted to say a good tech should be just like me,,,, but I won't say that... (big dumb rednecky grin)
I have to agree, it is far more important to know what you don't know (than it is to know it all) and not be afraid to ask, but that is not what any customer wants to hear about.
A good first impression (same like a salesperson) and a good attitude are always important, and understanding that we are selling all the time, count high on my list too...
I guess a smile for everyone, and thick skin to not be offended, and a lack of the sense of smell help when you have to work over by the dumpster are all good attributes in a service tech...
I find that the kind of people who, when they were kids, never had -enough- Tonka toys make good techs, as do those who, when they were young, tore stuff apart to see how it worked also make good techs.
Naturally a good set of tools, and the willingness to add to their tools as budget allows are also as important, as is pretty fair "mechanical aptitude" (they MUST know "righty tighty, lefty loosy").