If you're there for a while could you not do all of the things?
It would depend on the time of year and the day. Lately it's getting dark around 3:30pm so that's not a whole lot of light in the day when it's already quite overcast and dull. Then there's the tide, which will quite quickly catch you off-guard if you're not paying much attention to it. There are two ways to enter/exit the beach, but it's quite a long beach, and the tide can quickly cut off access to both sides.
I think it would be best to go there during spring or summer rather than the middle of December. :^)