All you need is good quality layers from kuiu and firstlite. The halstead fleece with the puffy from firstlite is a great combo from firstlite. Light shell and gloves, with layers on your lower section. Good to go.
I agree but backpacking in is really hard when it's raining to carry all those layers up switchbacks into the wilderness. I'll be running icebreaker merino wool layer, first lite chama, first lite Kanab, then when sitting in meadows the ECWCS cold weather layer on top. Be running that for 10 days in the backcountry with the goretex rain gear when it rains which is most of the time in September.