So I think you're saying that it's not wrong that Steph has flaws
Pretty much. Unfortunately for her, Steph's flaws cut to her fundamental abilities to operate on the level of somebody like Tim as a superhero. That gives her very different conflicts than, say, Tim's struggle about becoming too batty, or Dick's conflict about trying to be Bruce.
If Tim and Steph had stayed adolescent forever (a possibility in comics!) the day of reckoning could have been put off, but with Tim moving up they kind of pushed the issue. Sometimes I think of it as if, like, Tim and Steph had met auditioning for American Idol. Tim might say he doesn't want to be a singer professionally, is only doing it for whatever reason. But the second he opens his mouth Simon Cowell (Bruce) recognizes him as a professional and it's welcome to Hollywood. Tim was never really going to quit. Steph might seem the more enthusiastic of the two and she's eager to learn and work, but she still gets the "You will never have a singing career. Go home."
I admit to me what I see as her conflict makes her compelling. There's more to a character than how well they can operate like Tim. If she's happy operating on the level she's at, she can own that. Or else carve another role for herself. It has to get beyond just defying Batman (and now Tim--a boy younger than she is!)--again it's like they think that's the only way to show a female character is strong when sometimes it's the opposite.
It funny reading that stuff again makes me again think how weirdly Bruce treats Steph. It's like if he learned a lesson with Jason his solution was to act like as long as he continually tells Steph she shouldn't do this he has no responsibility, like he's just keeping her at arm's length. He discourages her, but it always sounds arbitrary, like maybe if she just works hard enough he'll eventually approve of her. When he gives her tests that she fails it seems more about confirming it for himself than showing her if that makes sense.
Heh. This makes me think it's good she never has much to do with Dick. Seems like he'd be a lot more straightforward with her and we can't have that. Tim, meanwhile, seems to have repressed any serious doubts about her for years until inspired by his rotten emotional state at the end of Robin. For him it's finally saying it; for her it just sounds like "I'm angry at you. Stop being Spoiler and I might be less angry." Talk about stepping into Batman's role.
I do think that Fabian N. wrote Jason with similar limitations, at least. But then other writers seem to think Jason could be a contender for the cowl...