It's interesting that those most obsessed with realism tend to forget what realism is. It's not crack whores, kids molested by authority figures, and people more interested in money than love. It can be, but usually not in the same group. The problem is that too many people think that noir is reality, and forget that there is something to actual real life.
When you write, you need to keep in mind that there is something to basic reality. It's interesting how many characters have tattoos, prison sentences of which they are completely innocent, and have been corrupted by their hard lives. After a while, it gets pretty boring when Rocky Road becomes vanilla.
The super-agents of the past are ironically more believable than today's rock-hard anti-heroes. The super-agents had more grounding, recognized the sacrifices that they were making, and were actually more rounded. They had friends that they could count on, acquaintances that they weren't sure of, and enemies that could ally with them if the situation warranted it. In a weird way, Doctor Doom is a far scarier villain simply because he can be more interested in pursuing his goals than the Fantastic Four; sometimes what the Fantastic Four does doesn't really matter in hi s plans, and they've been really miffed about that for some reason.
Today's anti-heroes can't trust the ground that they walk on; anyone can betray them and usually do. It's fine to shake things up every so often, but when you do it every other strip it loses its impact. You need some cement in your strip, something that can be counted on; the protagonist needs something that he can count on, something that won't change. If the only thing that can be counted on is that people can be bought or be petty, then there is no reason for him to act heroically; why should he risk life and limb for a few thousand dollars when what he does won't matter in the long run? Salvation sounds great as a motivation, but it's hard to believe in Heaven when you've only known Hell.
I hate using my own comic as an example, but the strips I'm most proud of are the ones where Detective Tate is with family, when he gives Simon a hard time about being his wife, or where people are just enjoying each other. I'm not afraid of the combats, but the familial scenes are important as well. It's not that those scenes are padding, my any means; those scenes are necessary to show that there is a reason why they fight so hard against what they fight.
The ties that bind can liberate you in the right circumstances...