For me, future-proof means it's easy for me to maintain. There is just far too much here I find unnecessary to make it easy for me to maintain.
But then again, I find designing websites in Photoshop silly.
As for designing websites in photoshop, at work we do it in keynote. It works surprisingly well and you can use mocks for presentations too! reference -> http://blog.swixhq.com/designing-swix-with-keynote/
I'm not designer, I wouldn't even class myself as a developer, but like everyone else I have a few web projects on the go. I've been searching for a low overhead way of getting a design mock-up down and your keynote idea hits it on the head.
Really being a hacker, I just want to mock-up a design that isn't butt ugly and for the tools to get the hell out of my way so I can start cutting code.
Check out http://keynotekungfu.com/