Last year there were some very selective fish (even in the early spring) in an area that we frequent. I think you were out with Art the days we fished it.
If you end up heading to that location with us and conditions are similar you're going to need 4-5" sand eel patterns with a very narrow profile. Silver or white on the bottom. These sand eels had a very blue back, not the traditional olive that is normally found (the color was similar to the AMEX logo up on the "donate" tab at the top of this page). Flies should be weighted to fish in 2-4' of water. Long gummies worked well but I hate fishing them.
Having the right fly was important with these fish but presentation was the most critical thing.
You're initial post was right.... Don't over-think it. In May 95% of the time you'll be chucking a clouser.
Hope to see you up there... I'm doing everything I can to make the trip but it's still up in the air right now.