I sail at the gap regularly -> my main concern is to not go out when it has rained heavily within the last few days as there are lots of sticks in the water, and the water isn't safe to ingest ( ask me how I know...

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I am leery of big-outgoing-tide as there is quite a bit of water moving flowing out. It is possible to sail, just stay out of the channel. You are on your own with no one to see you drift away.
A nice surprise is the depth - at low tide you can stand up almost everywhere (obviously not in the deep-blue). Some places are so shallow you will hit the bottom.
SE is really good - no wave riding, but there is some good jumping action; there is typically flat water with a ramp.
Sourtherly can be ok wave riding if there is a bit of swell around, but somewhat gusty on the inside - better to choose a larger board.
NE'er is very rough water, quite gusty... it has to be East-NE to be ok, but still quite rough.
I haven't tried the winter SW'ers.
If the wind is SE you can rig up at the Motorboat club and sail across on a single-tack; otherwise rig up at the Cadets and walk across. Do be aware of the depth of water across the bar. You can also launch in the Pond and sail+walk up... it is bit of a mission, but it is possible.
A "nicely powered" sail size on the inside or in the Pond, will be very powered up on the outside - typically there are a few knots more.
Best board choice is freewave to match the sail size. Since it is flat-water a slalom board is great for the big airs.