IMHO I wouldn't be too concerned, particularly with a soft grounding. I have an old mentor whose favorite saying is " You havn't been around if you havn't been aground."
I'd only be concerned, really concerned if the keel were distorted as it might affect performance.

Guys, that keel is indestructible. No need to repaint until you repaint the bottom for your normal maintenance. As they say in New Jersey, fuhgeddaboudit.

In a hard grounding, it is the keel's attachment to the hull that is vulnerable; but a 'gentle' soft grounding won't hurt that. A soft grounding, say on a shoaling sand bar, can expose the rudder to damage. For example, if you wind up on a fairly flat sand bottom, winds and waves could twist the boat around and bend the rudder post. Backing off, with a tow pulling from astern, can certainly damage the rudder. The C36 rudder extends nearly as deep as the keel.

You're lucky in your area you had a 'soft' grounding. Many others have experienced *hard* groundings in those waters, where you can go from 600 foot depth to on-the-rocks in about 2 minutes. When I used to teach sailing up there, I gave my students the Rule: you must be able to put your finger accurately on your location on a chart within 3 seconds. ALWAYS know where you are on the chart.

Larry..... please , everyone on the right coast knows "fuhgeddaboudit" is a common Brooklyn expression (from whence most New Jersyits sprang at some point).

Haha, I ran aground like three times in one day when I moved my boat from Newport Beach to the back bay in San Diego. The bay is like a mile or two wide back there, but is only navigable in a tiny waterway marked by signs I had never seen before, and that were saying the opposite of what I thought they were saying. I asked my diver to take a look at the damage. His description matched your description, but he said not to worry because "your boat is built like a tank" :o)

Needless to say, I broke out my Chapman's and began studying marine markers in earnest after that one!