HARRY POTTER SHOULD HAVE ENDED UP WITH CHO CHANG...period.
From the moment he first laid eyes on her, Harry Potter fancied Cho Chang. His stomach always backflips for Cho. IT ALWAYS DOES. He clearly likes her and she clearly displays interest in him.
Both Harry and Cho are instantly attracted to each other when they first meet on the Quidditch pitch at Hogwarts.
The reader feels the excitement from this point forward and wills their character on to success with his girl. Cho is the ultimate and incredible, pretty and lovely girl and one whom we see a clear chemistry with Harry.
She is super nice to him from the moment they meet and wishes him well in the Quidditich final and his stomach flips yet again
Throughout the entire series there is chemistry. It's there from the start and blossoms into a beautiful flower. We become part of this magnificent relationship in the making and the reader wants Harry and Cho to be. In the fourth book, Cho s also pro Harry (refusing to wear the Potter stink badges) after he is selected as a champion, friendly to him in the corridors, and wishing him luck. She is not joining in in all the anti Harry behavior of others. Note also, with Cho, the relationship is never about his fame, unlike others who talk to him or try to impress him.
Harry often dreams, fantasizes or imagines Cho - seeing her face through the crowd of supporters, seeing her being impressed and excited by him, seeing a future with her. This is a recurrent theme.
Harry always wants to ask CHO to the Yule ball. She is also genuinely sorry at not being able to say yes to go with him. Harry doesn't even think about Ginny at all in book 4. He doesn't even think about her in any way at all. She is not even a potential backup choice, Yule ball or not. He opts for Padma. To him, Ginny is like family. Harry essentially becomes close to the Weasleys, a friendly family who virtually take him in as one of their own. There was more of a spark between him and Fleur than Ginny.
Everyone sees it
Hermione, Ron, Ginny, etc, all see that Harry is attracted to Cho. Hermione mentions this in the books. Both she and Ron walk away to give him space in the films to speak to Cho. Harry hangs behind to try and get to speak to her before Christmas. Hermione notices how Cho couldn't take her eyes off Harry.
What about Harry and Cho?.....Well she couldn't take her eyes off you, could she?"
Cho always smiles and waves at Harry. She gets excited to see him and is often breathless/energetic to greet him. She also moves to inform him about Valentines Day, clearly wanting it. Maybe she thinks she needs to initiate given his nervousness in book 4. Cho also initiates the first kiss.
Cho might at a certain point get upset about Cedric, whom she shared a very brief relationship (though not with the spark or charm of her relationship with Harry) but then so does everyone, including Harry. Once she accepts Cedric's demise, she learns to accept that is all right to accept her genuine attraction for another.
Indeed, given her reaction to Harry asking her out in book 4, it appears that she would have certainly said yes to Harry, had he only gotten to her first.
She really does like him and couldn't go with him, having already said yes to someone. On top of this, any mixed feelings are down to anger and shall we say geopolitical wizarding events where many people (including the wizarding press and many at school) believe the lies and Harry to be mad/dangerous and he becomes disillusioned and stressed. However, at no point, does Cho ever turn against Harry or betray him. She clearly likes Harry a lot in book 5, just as she has when they first met. He really likes her too and there is a contuining developing chemistry, chemistry which existed since the start. She defends him, adores him, tries to look for an excuse to spend more time with him. She speaks up for him. Harry wants to impress her. There is a lapse in book 6 where they don't ever meet. Even in book 7, when Cho meets our hero, he is excited to see her, just as she is to see him. She wants to help him against the bad guys. A jealous and possessive Ginny intervenes however. Why would she do that? She clearly sees the chemistry between them too.
Quod intelligitur esse! - It was meant to be
The reader feels and wants Harry and Cho to succeed. Even in the films, we see that spark and magic in the air. We will Harry on and get excited to see Cho in his life.
If Harry is to end up with anyone from Hogwarts, it has to be Cho.
Ginny is not on Harry's mind in any way whatsoever. Ginny tbh likes him for his fame in book 1 and 2 and also having been saved by him. She is like his sister. And any interaction is based on being essentially part of the Weasley family. There is literally no chemistry with Ginny compared to Cho Chang at all! It feels so forced. Ginny also is clearly possessive preventing him from going with Cho in book 7. And Cho Chang was much more fun, cool, nice (e. g. didn't make fun of Fleur or others for that matter) and hot than Ginny. If he is to end up with someone from school and not meet and settle with someone else he meets after Hogwarts, then Cho is Harry's girl.
The chemistry with Cho developed. From instant attraction on the Quidditch line up, the Hogwarts Express, around school, in person with the flirting and banter, on dates and even in book 7 seeing her again, it was there for all to see.
Cho Chang: Harry! I love you.
Harry Potter [smiling]: I know."
Quod Erat Demonstrandum