I don't think there is such a thing as an Objectivist sense of life. There is an Objectivist philosophy, and Ayn Rand had her own sense of life, but sense of life is too individualized, too personal, for there to be an Objectivist sense of life. However, too often people conflate the Randian sense of life (which I don't particularly like, by the way -- more on that later) with the Objectivist philosophy. Wrong. That's the kind of thinking that leads to what a friend of mine used to call Howard Roark syndrome.
BTW, if you look at Rand's descriptions of Roark and Galt, you'll see that Rand's ideal men are portrayed as extremely relaxed -- there's this scene in the Fountainhead in which someone describes Roark as tense and he laughs because as the person says it Roark is lolling on the window-seat or whatever like a cat in the sun, utterly relaxed. And Galt's is "the face without pain or fear or guilt", etc. However, her heroes come across as tense, somehow, because that is *her* sense of life, in large part (someone I know say that Rand's sense of life was not benevolent but defiant). But Roark and Galt are not that way.
I guess I don't see Objectivism as a philosophy of control, even of active self-control in any repressive or tension-causing sense. "Howard Roark laughed." He didn't grit his teeth, he didn't get all worked up -- he went for a swim in an abandoned quarry, and he laughed about his troubles and the obstacles he faced. He was relaxed about it, took joy in the world, and lived his life as the unique being he was.
I think there are many ways to live as an Objectivist, many ways to be. If you go to an Objectivist conference, you will find all sorts of people -- hippies, straight-laced people in suits, rich people, poor people, actors, engineers, artists, computer jocks, etc. All that unites them is the philosophy. Each one has (or should have) his or her own sense of life, personality, special traits, idiosyncrasies, and so on. Back in the 60s you found a lot of people in the NYC-area Objectivist movement who wore capes and had long cigarette holders and so on, trying to be little Rands. But that's history.
So is there anything special about being an Objectivist? Should I be more likely to find a certain kind of person (in terms of sense of life) among Objectivists? I think in general that Objectivists have certain ethical traits in common -- they tend to be honest and rational and so on. And I have found some wonderful people who are Objectivists. But I've also found some creeps and some people who are just screwed up.
Certain people I know and like exemplify what I think of as the Objectivist ideal better than others. But is that just because I like them? And is what I think of as the ideal really the Objectivist ideal or is it just my ideal? I tend to think that I'm a good example of an Objectivist, but maybe that's just because I think so well of myself. :-)
I think of the Objectivist ideal as the kind of person who is at home on earth, open to reality, benevolent, full of thought ("thinksome"), calm almost to the point of serenity, yet passionate, open to emotion, open to reason (not dogmatic), intelligent in the sense of using one's mind and being curious about the world, "centered", not seeking the approval of others, friendly, honest and straightforward, humanistic, creative of value in the world (in whatever sphere of life one chooses), in love with and passionate about life in all its particulars, interested in conversation (not argument), and so on (I'd like to think more about this, I'm sure I could come up with other qualities). But is this my ideal or the Objectivist ideal? I don't know.