You've got to get your line below the wash or it will be a pretty miserable day. As far as spots to try, your best bet is to hit one of the local shops and ask for some up to date information. Fishing along the Outer Banks can change rapidly and the spots you had success at last year may not produce the results that you want this trip. There are many places in North Carolina that offer flyfishing in May besides the Northern Outer Banks. Any fly that is slender is going to get bit at one time or another.
Chartreuse is always a good color to start with.
I often tie mine with a blue or an olive back. As for recommended patterns, if you are already using Clousers and Deceivers you can't go wrong. I have developed a new pattern that kills on schooling Spanish mackerel, bluefish, bonito, little tunny and ladyfish. I call it the Bullet Proof Baitfish, but I am not ready to unveil it on the world yet. I am still working out the fine points.