Good point! Actually it just happens to be, I was intending this for Western Montana, elk/mule deerLittle info on your intended use will help refine the answers. For western montana this is what I use from August through December.
short sleeve first lite 150 wick or Sitka core lightweight or KUIU 118
Kuiu Peloton 97
Kuiu Peloton 240 hoody
SKRE Ptarmigan Hooded
Kuiu Chugach Rain Jacket
Those above get me through just about everything August to mid October or November. Once it really gets cold and wet or snowy I’ll add a Sitka Jetstream Jacket. Once I add the Jetstream the rain jacket is probably coming out of the pack. Now I don’t do much sitting and glassing or I might add another puffy late in the year. Wind is the biggest challenge for me and the 240 hoody is really the only piece out there that acts like a fleece and stops almost all of the wind unless it’s really blowing hard. I can always adjust for temperature but the wind will cut through the best layering system without something stopping it. I don’t like wearing my rain jacket to stop the wind unless I have to do the 240 and Jetstream take care of that.
Sitkas closest system would be
Core lightweight SS
Core Heavyweight or midweight
Timberline jacket (not going to breathe like a 240), I would probably do a kelvin active here instead but it stops zero wind because it breathes so well
Sitka kelvin lite puffy (not as warm as the SKRE,
Maybe close with core heavyweight and kelvin active)
Cloudburst rain Jacket could also do the Dewpoint
Add the Jetstream late