Congrats, that is a really nice laker and I think your right about the available forage. The alewife is probably one of the big fish keys but an abundant plankton population is a required food source for their numbers and I don't believe it's sufficient but it can be increased by pumping water from the river into the Valley. It's also necessary for the state to consider regulations if we want big fish and that should include doing what you did, take a picture and put it back for another day. Here is a link of a Ct. study that is to me an eye-opener and the lake that I told you about had the numbers of big trout go way down.
http://www.ct.gov/deep/lib/deep/fish...gt_2014-15.pdf