Nice work!! Great details.
By exposure Quark means, you could allow more time on the image. eg 30secs. He may have missed though, that you are using a Point and shoot not a DSLR, so I would image you can not do long exposures...
Your exposure time looks fine to me though.
You could definately pull out more detail, through processing, as you said.
This is a quick re-work. Not necessarily better, just my view.
Slight sharpen, Curves, Switched to B&W (to remove halo), Contrast adjust and Noise reduction.
Turned out alright, your initial shot is tops though!!
Keep 'em coming!!
