When I was younger, I always wore heavy leather hiking boots. I loved big leather boots. They made me feel invincible. The problem is, weight on your feet matters more than weight on you back, and then there is this whole growing old thing.
First step, I just started buying boots that weren't all leather. Then I started looking for boots that weighed under three pounds. Then I met Dave, who is my current hiking partner. I'm currently waiting for him to get back from the CDT. We talk gear a lot. Apparently, what is big with long trail hikers, especially the AT, is trail runners (shoes) that dry quickly. His current shoe of choice is the Altra.
I'm a footwear guy, so I now have more boots and shoes than I could wear out in several lifetimes. I have shoes and boots still in their boxes and never worn. Here were some of my considerations, when I was shopping: On the one hand, running shoes are lighter, cooler, often have better shock absorption, give better foot articulation, and are just more comfortable. On the other, boots offer some ankle protection on rocky sections, keep debris out better and, if waterproof, can keep your feet dry when rock hopping across a stream.
I'm currently using trail runners on some hikes and light boots (around 2 pounds or less) on others. I don't think waterproofing on trail runners makes a lot of sense since water comes over the top so easily. Waterproofing just holds the water in. But on boots, I tend do go for waterproofing because on most stream crossings, the rocks I step on are only barely submerged, so a waterproof boot can keep my feet dry.
Don't think there is a one shoe that does it all. I'm inclined to use boots in the spring and on rocky hikes, and trail runners in summer and fall, on trails I won't twist my ankle. And then, all it takes is one hike to change which way I'm leaning.
Sorry this is so long. Like I said, I'm into footwear. I have a hard time passing up a bargain too.