Question: introducing characters

One of my writing weaknesses is introducing characters - especially the bit-part, walk-on characters who are only with the reader for two or three pages. For instance, can you visualise this person from the text I use to introduce him? Should I be using more details? Less? What sort of information are you hoping to get upfront when a story introduces a chorus-line actor?

Levruekkas the Springman was older than many, making him easy to identify in the gang of workers who were busy hauling one of the larger generators out of the water. A semi-circle of loose, roughly platted, unfashionably long hair edged around his dark, bald crown, giving him the appearance of a outlaw out of legend. The Guardsman knew that the Springman went to some length to cultivate this image, probably because it was good for business. The other men were shorter and stockier – almost certainly Servants – four of them hauling on pulley ropes with another two, no three, still in the water. All the Servants were naked, and given the age and wear of the Springman's short tunic he might as well have been naked too.