I'm a fan of "Position and hold" because of the correlation to other uses.
"Traffic holding in position downfield..." during a runway crossing clearance tells you exactly what you know based on being previously told to 'position and hold'.
"Taxi via Alpha, Bravo, hold short runway 35" tells you to STOP short of something, as in STOP MOVING. "Wait," is somewhat vague.. almost an indefinite modifier.
"Line up and wait," has no other real reference other than the actual event at hand.
Position and hold references other ideas in use on the airport surface. I think it makes for better communication.