I'm not very familiar with the Carman's River system but have fished both upper and lower Yaphank lakes. My success has been better in the Lower lake simply because it was the first one I had tried and the one I know best. I agree with what has been said; the lakes are both easier to fish, early in the season but both are pretty cold so, they can be fished from shore into June. My preferred way to fish most LI waters is by wading but you do need to be careful when doing so, as previously stated. The decaying plant matter makes for unreliable footing, appearing to be "bottom" in 3 ' of water but turns out to be 3' of muck in 6' of water!!
Even after weeding up, topwater lures work well, especially, after dark, as do worms, both real and artificial. Buzz baits and spinner baits can work but I've never had success with them after dark or on bright days except at Blydenburg. Before weed-up, any technique that works anywhere else, will work here. I use artificials, almost exclusively with plastic bodied jigs my favorite all around lure, because of all the weedy conditions. I often use the plastic jig bodies on a baitholder hook and split shot from a boat when I can see "holes" in the weeds. (beware this technique when in pickerel waters!).... same with the ultra lite versioons of plugs. It will get costly.
When plugging for pickerel, use big plugs that are of one piece construction. Picks have cavernous mouths and egos to match. They will hit lures they couldn't possibly eat. I would use a wire leader if using a 4" plug for picks. When I go for picks, on purpose, I won't use less than a 6" plug or a 9" plastic worm.... a word to the wise; if using the 9" worm in weedy waters, use very heavy line, or, at least a very heavy shock tippet. Picks get big on LI, even in small ponds.
At Blydenburg, the bigger, sophomore bass, hole up, right against the bank, in the shade when the sun is up (6"-12" of water with 5'-6' nearby). These are 2# fish and you will, likely, find large (1# and up) bluegills in similar spots where the water is less deep, overall (max 4' or so). The biggest bass will be in the prime deepest water under the weeds of on structure that provides shade to them in the deeper water.