If I had to pick one down jacket for everything in New England, it would probably be my Marmot Zeus or a similar Patagonia Down Sweater. Heavy enough for an around town car jacket down to 20 degrees F, but light enough to be perfectly comfortable up to perhaps 35 to 40 degrees. Packs into its own pocket, not as small as an ultralight, but small enough to put in a backpack. And, looks better for around town than the ultralight hoodies. Weighs about 14 ounces with 20 denier non-shiny polyester ripstop.
I think the Zeus is probably in the 4 ounces of down range, so something like that or the Montbell seems sensible.
I also have super warm baffled down jacket with 10 ounces of 800 fill down. That's fantastic on very cold winter days 0f to 10f, but too much jacket most of the time.
REI has them on sale for $120. Sierra Trading Post has a couple of bright colors for $92 with their e-mail discount codes.