The kuiu yukon pants are good enough that I regularly wear them as my only outer layer, insulation beneath to suit temps. I've used them for up to 3 days as my only pant that I carried, w/ no sun in the forecast. I would quite happily carry those and something for sunny or high output approach hikes.
I hunt with a few guys with Sitka, everyone of them ends up alot wetter then me. None of it's their more recent gear, so I dont know if something has improved.
I've also considered a rain poncho instead of a typical rain jacket. If I was always going to be wearing my big pack, and I knew it was going to be consistently wet, I think I might go try something like that. Typical rain jackets just can't breathe well enough, especially with a big pack on, during high output activity.