It depends upon the usage of your image. If you're going to post it online, sure crank it up until you see halos, then wind it back a little. However if you want to make a large fine-art print, it then depends upon what you want your image to be! I do shoot an IQ160, but I think this applies to all cameras
For example:
Is a very high contrast image with most of the foreground in shadow to hang onto details in the sky. The clarity slider, set to punch, was cranked right up and gives a wild look, which is entirely the intention. When looking at the print the usual comment is, "is that a painting"?
This one:
Required a tremendous amount of playing to get the layers in the image correct and to avoid nasty halos, especially along the boundary between sky and far mountain. Obviously some of the image I was attempting that high clarity look and in the foreground it was much reduced. Note there are apparent halos along the left land vs sky, which is jpeg compression artefact.
I recall on that last image that the sand went quite orange and whilst had some interesting warmth in foreground vs cool behind type of punch, I really felt it was wrong, distracted from the main subject and wanted to emphasise the sun-bleached sand and intense sunshine. I can't recall now how I solved the problem, perhaps instead of punch used neutral!
So the consultants answer is, it depends.