First of all, let me state that I don't feel as though I am any boot/shoe expert. I just know what works and what doesn't work for me. I was out along one part of the PCT last week, and I noticed what others were wearing for footwear.
I feel that if you can get your total load really light, like 25 pounds or less, then you can get by with a lighter shoe. I have some Inov-8 model 195, but then my feet start feeling the extra flexion after several days. The heavier models would protect your feet more, but they probably won't be as cool (in a temperature sense). If you are carrying 35 pounds, then I think you want something heavier. You also want to think about how much time you spend sloshing through streams.
On a dry year, a well-developed trail like the PCT may have lots of bridges and rocks for stream crossings, and if it doesn't rain much, you don't need boots that drain so rapidly. OTOH, on a wet year, you have those knee-deep streams (or worse), so the rapid draining is a bigger deal.
My Inov-8 shoes are a half size up from my normal size. At first that felt funny and loose, so I started wearing very thick socks. Then after a couple of hard days, my feet swell slightly, so I can shift over to medium thick socks. Thin socks are not comfortable to me. You really have to try out this stuff to find out what works for you.
Of the hikers going southbound, the majority were carrying bulky loads of 35-40 pounds or more, and they did not look like happy campers. Most were wearing what I would call standard footwear. Only as the load was reduced did the lighter footwear show up. Then one guy had about a twenty pound load, and he was wearing minimalist footwear. You would have to get his opinion on how those were working out, but I was not impressed.