She hasn't, actually, been to Hell.
She asked to go once, when she was twenty eight years old. She'd been arguing with Arazni, about whether she should be aspiring to become the perfect and inhuman Lawful Good god of marshalling Heaven to fix everything.
"Come with me," Arazni said, and Iomedae permitted the Plane Shift - even then, even for Arazni, it was difficult to make a spell land that Iomedae was inclined to resist -
- and when she lifted her eyes to the glittering spired sky and knew herself to be in Axis, she closed her eyes again, because she didn't want to spend Aroden's intervention budget wantonly.
"It's My budget," said Arazni, tiredly, "and not even all that much of it, and I am spending it towards my goals; I think there is something here it is dangerous towards your goals, for you to be unwilling to look at."
So she opened her eyes. It was beautiful, but she'd known it would be. Alive and inventive and alien and relentlessly richer than it'd been the day before. Much richer than Heaven, which was presumably part of the point Arazni had brought her here to make.
"I think," Arazni said, "that it is bad for people to aspire only to glorious death on the battlefields of Golarion and then glorious death on the battles of Abaddon, or wherever else Heaven sends them, and never to imagine any future so compelling to them that it'd tempt them from sacrifice."
"I have never aspired to death," Iomedae said.
"You want to be a god who -"
"I'm going to die," Iomedae said. "That's not - I am not denying that the plan I have described to you constitutes death. I meant that the aspiration is to create the right kind of god, and dying is a thing that will happen along the way, and it's a different motion, and a less destructive one, than aspiring to die. No one else makes the distinction but it's - a really important one -"
"I continue to think that you are reluctant to imagine a world good enough you would be tempted to continue living so that you could have it."
Iomedae shook her head and opened her mouth to object. And then reminded herself that Arazni was in fact much older and wiser than her, and spending something important to try to make this point, presumably because it was an important one. And tried to - imagine that it was true, that she was reluctant to imagine how good the future could be in part because she was afraid that really believing in it would make it harder for her to do what she has decided she is going to do.
Okay, maybe it was a little bit true.
She tried, then, for the first time, to imagine an actually good future. She stared out at the streets of Axis, and was silent, and -
"It doesn't matter," she said eventually. "However - however good it is, if it is more likely to come about if I ascend properly, then I should do that. It's a multiplier on everything else, not a - reason for selfishness. You were right that I was reluctant to think about it, and that was silly of me, and I am grateful for the prompt to be less of an idiot, but - but it isn't the kind of thing that could change anything."
"I think," Arazni said, "it is a reluctance you might not have had, a mistake you might not have made, if you weren't so set on - dying. I think that since you are asking of yourself a thing people generally cannot ask of themselves, you are instinctively wary of putting too much pressure on the convictions that seem to be permitting you to ask it of yourself, and I think it's a knot inside your head that'd be gone if you permitted yourself a bit more - selfishness, if you want to call it that -"
"What do you want to call it?"
"Humanity."
Iomedae looked out at Axis. "This is the wrong place," she said, after a minute. "If we're going to talk about whether I should permit myself more selfishness. If we're going to talk about that you should arrange me safe passage to Avernus, and we can go there and talk to our hearts' content, about how comprehensible it is of us to be selfish."