Right!
Usually not much mackerel fishing going on in mid winter @ GSPPier ;-)
Your 15# braid/ 8# leader sounds about perfect.
I often use that setup (even 20# braid) as the main line with 10#-12# fluoro or clear mono leader.
Only thing is you may have to go with a longer leader (for sheeps) if the water is extremely clear and calm.
And there might be some bluefish around, but all you'd need to do is heavy up your fluoro leader or add a short trace of wire for them.

