Soldato
those pants will be perfect! in terms of socks I'd suggest Stance! Honestly the best thing I've ever worn! only need about 3 pairs for a week or so, backpack I'd go a dakine heli bag they small and sit nice and tight on the back. As for back protection that's up to you, If you think you'll need it go for it, However I do think for the decent stuff it's expensive, But you can't really put a price on safety.
They came in the post yesterday. I'm a gym rat so have a rather annoying waist to hip/thigh ratio, but with the velcro adjusters on the waist they're not slipping down me too badly. They're a bit long as I'm a 30 leg but I guess that doesn't matter given how big the boots are.
I got a couple of 100% merino socks as well as two 100% merino base layers, with the plan being to alternate between them and hopefully they'll live up to the 'won't whiff' hype. Just need gloves (and travel insurance) and I'm more or less done: they're the one thing I need to really try a bunch on at the same time to see what fits best so haven't ordered them online.