What is the profile of a great Service Engineer?

I was thinking about my family, and their personalities and traits, and wondering who amongst them would make a great Service Engineer.
After some thought, I was surprised how easy it was to rule people out.
And much harder to think of anyone I thought would be great.
They all had one or two of the qualities, but there was only one who had them all.

So, what sort of person makes a great Service Engineer?
What are the key qualities for a successful Engineer working in the field?

Interested in:
Technical issues
Structure, rules, and systems
Mysteries and detective stories
Fixing things
The unexpected
Adaptable, resourceful, and hands-on
Good communicator – good listener – able to ask good questions
Quick thinking
Detail oriented and methodical
Patient / calm / unflappable
Is constantly learning
Never standing still
Wanting to become an expert, and then remain expert in their specialism and the equipment they support

If you had to hire someone to cover for you?

Which of these qualities would you want?

And what would you add to this list?

And why?

Worth Sharing!