I haven't been that keen on Morrison writing Wonder Woman though -mostly because the women that I'm familiar with Morrison writing as lead characters are all written as psychological cases (Crazy Jane, Ragged Robin, Boy, Emma Frost and Jean Grey are all the ones that come immediately to mind) and for me, Wonder Woman should be as far from that as possible. I suppose that just because I can't think of a woman he hasn't written that way it doesn't mean that he can't write a woman that way, but I'd like to see it first I guess.
I think what's killing me about this comment is that I'm not sure what he means by "psychological case." You'd think he means someone who has a severe mental health issue, but there's the inclusion of Jean and Emma. Back in New X-men Morrison certainly delved deep into their psyches, but the major psychological issues on the team belonged to Scott and Professor X. Emma and Jean were having a relatively normal conflict, the sort of thing that might happen between two mental health professionals: one woman was unable to effectively counsel her husband while he had a psychological breakdown because she was far too close to him, and the other woman was taking advantage of that psychological breakdown to begin an affair. The confrontation issue--when Jean came home and locked Scott out of the room while she took Emma on a tour of her issues--wasn't the same as delving into Crazy Jane's past or the 'Nuff Said issue where they entered Professor Xavier's mind--and both women displayed the mental health needed to survive on his battered psychic landscape without falling prey to the dangers there--and saw just how messed up he was.
Even at her coldest in Morrison's run Emma is not portrayed as a complete sociopath, instead she's a woman who is willing to cause a great deal of social trouble. Morrison did examine her mental health by giving her secondary mutation that would cushion her psyche from an extremely traumatic experience, as well as be a metaphor for her way of dealing with people socially--which is basically what someone of Emma's personality type does, they act cold and cruel to prevent others from getting close enough to hurt them--and he had Jean take her back into her past to remember exactly why she's unable to let people get close to her. Super-powers aside, Emma wasn't a "psychological case" as in a woman unable to function because of her mental illnesses, she was a normal woman behaving in normal human ways that are often hurtful. You could say a lot about Emma Frost, but you can't say Morrison portrayed her as insane. (Whedon did, though.) She was affected by the tragedies she witnessed (cold as Emma acted, there were several points that the hell she went through in Genosha was evident, and it was her strength of will keeping her together and not a lack of heart), and she was formed by the household where she was raised. She was perfectly healthy and functional, she just had issues like people have issues.
Jean was even saner. Surely everyone has at least seen a loved one grow into a different person because they become stronger. Sometimes it's a bit hard to deal with, especially when that loved one doesn't realize they're acting any differently. Jean had the power of the Phoenix again, and it frightened the hell out of many of the other characters. She was perfectly in control of it and didn't see the problem, didn't fully comprehend just how strange that seemed to the others, and at this high point in her self-esteem was further away from her husband's misery than ever. This situation is a really good metaphor for when someone suddenly discovers a talent or started experiencing success or just gets her life on perfect course while her husband is feeling lower than ever. There's a major disconnect in her perception of herself, and the perception others have of her, but she doesn't pick it up. This is actually even more compelling because Jean's one of the more perceptive telepaths in the Marvel Universe and she does know people are uncomfortable, but because she's at a high point in her life and because--unlike Professor Xavier and Emma Frost who seem to just invade whoever's psyche they want--she respects people's privacy and doesn't pry into their thoughts she doesn't realize just how removed she is from them at that point. The affair hit her like a foul ball in the back of the head while signaling the hot dog guy. She attacked, and as some women do verbally, telepathically zeroed in on the weak spots of her opponent and let her have it.
I notice this is a thing Morrison likes to do when he writes a solo book. He likes to explore the character's emotions and personality, but he doesn't do it like other writers do. The in-thing with Bendis, Millar, Winick, Johns and a few other popular writers seems to be to have characters explore their emotions by sitting, brooding, and talking it out with other characters. The psychological problems of the heroes are spelled out, stated explicitly by other characters, the narration, or the character themselves. Disturbingly often the writer finds a way to have someone assure the hero they area normal for having these issues and spell out the tie to your real life. Morrison rarely says anything flat out and takes full advantage of the medium and genre to explore the character's psyche through conventions, powers, events, and even staging. Bulleteer may be the most I've seen one of his heroes brood. She has doubts about her place in the universe after gaining superpowers and finding out her husband was actually an asshole, and she comes to terms with them by acting as a superhero, observing the weirdness of the universe and how others deal with it, and then verbalizing the theme of the book in a multi-stage fight that utilized a refrigerator and a car engine. Batman--who legitimately can be described as a psychological case under most writers--creates an entire other personality that leads back to the greatest tragedy of his life, and Morrison explains it sparingly with flashbacks. Shining Knight experiences a coming of age tale that literally involves fighting the perversion of everything she held dear as a child. And the underlying theme to all of these stories is that the extraordinary--the problems of the superheroes--are not abnormal psychology but are metaphors for the mental experience of your average human being.
Now, if what the commenter means is "psychological case" as in "case-study of human psychology" as opposed to someone who should be committed to a therapist's care, then yes Morrison writes most of his female (and male) leads that way. In this case I completely fail to see what's wrong with an in-depth examination of what makes Wonder Woman tick amidst her fighting beings from the future, the past, another universe or beyond the multiverse.
If he means the latter, I'm not sure what version of New X-men he read but it's not on my shelf.