You should throw a leg over each in your list. That's the only way you'll know if it feels right to you. Some of those are boutique brands and not always easy ti find, so it may be tough to get access.
You can always extend your cockpit with a longer stem, but I find I don't like the steering characteristcs of an AM bike with a long stem. I'm exactly 6' and usually like large frames with short stems.
I haven't ridden a Nomad, but as a general rule, SCs tend to have short cockpits relative to their frame size--probably not what you're looking for. In my experience, the same goes for Intense, but to a lesser degree.
The Rocky has their "Straight Up" geometry, which really does make long climbs easier. Since the Slayer is a longer travel bike with a long fork, the geometry can help compensate for the lower "climbability" of some AM bikes. You do lose a bit of stability on the downhill compared to some other AM bikes, though, but it sounds like you're more interested in aclimber anyway.
The Giant tends to be a good, solid middle of the trail kind of bike. Nothing extreme on either end. If you settle in comfortably on a neutral riding frame, this may be a good choice--you'll have to go for the large to get the cockpit room you seek.
I've never thrown a leg over a Pivot, but have heard mostly good things.
If you're looking for an excellent climbing AM bike with good room in the cockpit, you might want to add the Yeti SB-66 to your check-it-out list.