I'd avoid anything synthetic. As good as Kuiu, Sitka and some of the other companies are, they work until they don't....which IME isn't very long with normal usage.
You really may want to look into Filson. Their double Mackinaw Cruiser is simply awesome, but too heavy if you're hiking around all day and not real good for the layering theory. If you did go this route, you may just want to strap it to the outside of your pack when hiking a lot. It'll certainly last 25+ years, assuming you don't put it in a hot air dryer. If you're just wanting an outer shell, one of Filson's tin cloth jackets may be worth looking into.
