It sounds like you are doing everything right, the fish probably just are not there.
Here are a couple of suggestions though. Try a different stage of the tide, try down sizing your hook I like very small gold kahle hooks myself like a 2, 4, or 1/0. As far as teasers, things can go either way sometimes the teaser is too much and spooks fish other times it is vital. I like slide on bucktails in white or chartreuse preferrably with a little flash, spinner rigs are another setup I like. Often times though you need to get rid of the teaser when the fish get finnicky.
For the finesse approach try a few things. Small hooks(pay attention or you will get lots of gut hooked fish) for starters. I see you are using flouro, that is a big plus, but I'd try lighter material like 12-15lb. You may also want to try lengthening your leaders to 36''. The rigs you are tying sound right on point though, three way or fishfinder. I prefer the fish finder personally because you can let the fish mouth the bait, you just have to be cautious with smaller hooks so you don't gut hook too many. Seriously consider using spearing over killies, especially up your way, the bay is loaded with them in the summer.
IMHO it sound like you should already be catching fish the way you are currently fishing. It is probably the spot or timing more than your technique.
I see you are up on Raritan bay, where are you fishing? I don't know much about shore fishing up that way, but it is great in a boat. I hear a lot of fish are being caught around Sandy Hook and Bug Light tight to the beach in water that the boats have trouble drifting because of the depth. You might try heading up that way.