The galaxy is dangerous. If players never feel that sense of danger, then they will also never feel the same levels of triumph when they overcome it. If some people prefer to play their sessions safe, then I guess that's their prerogative. But I'll say that as a GM it would be mind numbingly boring to play with that group.
I think some of the (closet) munchkins here need to ask themselves one question: Which is more memorable and enjoyable for everyone at the table: A character who is role played as overcoming a flaw from some major adversity? Or a character who does more damage than everyone else at the table?
I personally love the flawed characters. They are more interesting to play as well as more interesting to play with (when it's someone else who is flawed). I have a player who decided to make use of the drugs table in EOTE and make his character a junkie. Knowing full well that this decision will have negative consequences (and his drug of choice gives him no benefits), it makes the stories that much more memorable and that character more memorable.
Hell. Who here has heard of Raistlin Majere? A powerful wizard from the Dragonlance books. Very popular in that world. While he is very powerful, he is also very weak and sickly. Prone to illness all the time. This is because that character was based off of a D&D character who the creator ended up rolling a 3 for Constitution (where the average is 10). Instead of whining about it, fudging it, or rerolling, he used that flaw and turned his character into someone far more memorable than "generic powerful wizard 4.0."
And also one last thing, never forget that a GM is not required to spend advantage on a crit. He can spend it in other ways. So if he's attacking with a vicious 5 weapon and the player already has 3 critical injuries, he's not obligated to crit (unlike most d20 games) when the dice give him the ability to.