I don't know that these things are necessarily true. For one, rumor has it that all sx-doms are "intense", but I don't think that is true in the sense that bright orange is intense. I think it's more true in the sense that deep violet is intense, dark red is intense, pine green is intense. Maybe some sx-doms are magenta on the color wheel, but for others of us, our intensity may manifest more in mental rumination, idealization, and strength of 1-to-1 bonding than in flashy fireworks - an intensity of heaviness instead of one of lightness. If anything characterizes sx accurately, I don't believe it's intensity of persona, but rather intensity of focus on one specific desire. Take the new Gatsby movie that's coming out - Jay Gatsby most certainly is an sx/so. The intensity of his focus is so strong that it transforms his entire life, taking everything in its wake, and he utilizes the social sphere as an arena to play out his obsession. He is an intense person, but remember that while huge parties roar in his mansion, he's standing alone outside in his lawn, staring at a faint green light in the distance. I really think that's more true to what sx/so is because we're always yearning - even if he were inside, he'd be trying to get that one woman away from the crowd. It's not really our selves that are intense so much as our desires are intense.
As for phobia/counterphobia, like you said, if pressed to choose, I'd probably label myself as phobic. I tend to come out guns blazing when threatened, but my attitude is really more phobic overall. I have a pathological need for people to like me! :c
Anyway, I don't know that I think any 6 will live their life like they're going to die the next day. If a 6 is living like they're going to die the next day, they're going to be planning their funeral, getting their will in order, making sure they tell all the people important to them that they love them, and so on... 6s are autoprogrammed to account for the future, so I really have a hard time thinking about a 6 who lives for the moment. I don't think they would be a 6.
Both of which points are to say, I don't see ruling out 6 sx/so for any of those reasons.
As far as sp goes, I'm not sure how our treatment of sp needs lines up. I was sp-coddled as a child and thrust into sp awareness, too, and it's certainly been a learning curve, but for the most part sp needs just seem to me like another thing on a checklist - gotta have em, so I try to make them appealing and a pleasant experience. As a 6, I'm careful with money. I'm a natural saver, I pay off my credit card bills early, and if my bank account gets too low for my preference, I essentially stop spending whenever possible until it's back to normal. I've never really been completely oblivious to physical harm, but I don't generally take extra precautions like kneepads when skating or anything, either. I'm claustrophobic - I hate/am afraid of planes, elevators, tight passageways, being twisted up in blankets, and being caught in any other sort of small space. I worry about crashing when flying, elevators breaking and falling, freak car accidents, losing my temper at work or getting caught doing something stupid and getting fired, and sudden medical emergencies - all things with low likelihoods but that would cause devastating damage in my life.