I spent ten years sailing two keelboats (20' & 26') without engines. It is challenging and somewhat restricting, but also rewarding. I didn't sail on busy weekends or holidays due to inlet traffic. I also used a long oar, but only in a calm. I found I could manage the inlet sailing with either wind or current opposing, but not both. On the south shore of Long Island summer breezes are pretty reliable. watch for sea breezes that start midmorning and end around sunset. Have good ground tackle. Keep a little food and water aboard, you might be becalmed overnight. Don't push right of way, be safe and considerate.