Thank you for all the info!
Yes we like to choose the evening before where we want to hike, if we dont have to apply for a site-specific permit. Keeps things interesting for us :)
For those of you who might be interested, we hiked the loop up Falling Waters trail, over Little Haystack, Lincoln, and Lafayette, and back down. There were a few mosquitos, no black flies that we could find, and we never needed to use our bug spray. Great trip overall! So I think in the spirit of the OP here, I would definitely cut back on the shelter in late summer, at least in the area we were in, since bugs did not seem to be an issue. Although perhaps we were lucky?
We did find some denatured alcohol (quart size) at the hardware store, but the summit shop next door in Lincoln sold it by the ounce. Did the math, to buy the quart was $0.29/ounce, the Summit Shop sold it for $0.30/ounce.
Thank you for the map recommendation, we did use that map that you suggested, it was great except that the fairly large river with water falls along the Falling Waters trail was no where to be seen on our 2006 edition, although it was on other hikers' maps. Weird!