I don't think the spreadsheet is overkill at all. Not only is it a great tool to keep the weight under control (especially when drooling over a potential new gear addition), but I print mine out as a checklist when getting ready for a trip so I don't forget anything!

Most of my prolonged rain experience is at high altitudes, with temps often in the 30's and low 40's (F). In those circumstances, it's more important to stay dry. You mentioned hiking the PCT, and those conditions can apply in many places there. On the other hand, at those temperatures you won't be sweating inside your rain gear, either! If the temp is above 55 (F), I also find that I'm better off just to get wet. Once my tent is up, I change into my base layer and (when I go out) wear the rain gear over it. My nylon hiking shirt and pants dry within an hour, even if it's damp outside. It looks as though we use rather similar techniques, but I won't go out without the rain gear.