traits of a Roman legionary

[Tarbicus]

You'd also have to observe how our man acts around those in positions of authority. How instictively he acts when a praetor or senator conveys a wish, directed towards him.

I don't think that would be any different to any other citizen, and bear in mind Octavian had a hell of a time getting the veterans to do what he wanted when it came to land allocation (meaning not to also take their neighbour's land as well). In fact, he didn't get them to do it at all, and he had to compensate the disposessed neighbours as well. They were quite capable of making their own minds up and were no pushover when they didn't want to do something.