Loki on Disney Plus was certainly a wild ride, and really shook up the future of the MCU. The show also made some choices regarding characters that were less than well-received by fans. One of the most controversial moments in the MCU was the decision to put Loki and Sylvie (a female Loki variant) together in a romantic relationship. A lot of fans found this choice to be uncomfortable and a little too close to incestuous for their liking. It wasn't as though this was the only way to tell the story; there were other ways they could have gone about the romantic relationship that would have made just as much sense.
The easiest answer would have been to just cut the romance and make their connection purely platonic. It still would have worked in the context of the story, as Loki doesn't make many friends, and it would have been just as emotionally effective if he cared as deeply as he does for Sylvie, but simply as a friend. However, there's also a way that Marvel could have kept the romance angle but made it far less uncomfortable, and it involves making Sylvie's backstory more accurate (though still not entirely accurate) to that of her comics counterpart.
In the comics, Sylvie Lushton is a kid who wakes up one day with powers that have been given to her by Loki, and it later comes out that he fully created her for his own chaotic purposes, and that her memories of her life before powers were false because she didn't exist before then. Sylvie moves to New York in hopes of joining the Avengers, and takes on the style and title of Amora the Enchantress, as they have very similar power sets. Sylvie is a magic user and utilizes her sorcery for many purposes, including mental manipulation, flight, teleportation, transmutation, and telekinesis. She eventually joins the Young Masters team, and encounters the Young Avengers in the Dark Reign comic run, going head-to-head with Wiccan and even rivaling his powers.
With a few tweaks, this backstory could have been used for the Sylvie that appears in Loki, without changing too much of the story. Making Sylvie more comics-accurate would have actually improved the show because some of the decisions the writers made would have made more sense in this context. So how exactly could Sylvie's character have been adapted for the show if it was more accurate to her story (at least, her backstory) in the comics?
In this version of the story, Sylvie could have actually been an Asgardian who knew Loki when they were both children. Perhaps she was one of the only friends he had growing up, which gives them a history and emotional connection before the show even starts, which makes it easier for the audience to buy into them developing feelings for each other in such a short time over the course of the show. Maybe in the normal MCU timeline of events (or Earth 616, as the main timeline is called in the comics), Loki doesn't give her powers, but in an alternate timeline (her timeline), he does. This could be Sylvie's Nexus event – being given powers.
Then events could play out just like they do in Loki, where the TVA shows up to take her, but she runs away and manages to jump around timelines and hide from them the same way she does in the show already, and has grown into an adult by the time the audience meets her. This way, the story doesn't change too much from what we see in Loki, and actually gives the audience a clear answer on why Sylvie was taken by the TVA, and her motivations remain quite similar to the show as it is. She hates the TVA for ripping her out of her timeline and stealing her life, and she could have essentially the same personality and powers as she already does in the show, but with a more interesting and clear backstory than just being a Loki variant.
This also gives her a much more believable connection with Loki, as they have that shared history. It also gives her a good reason to harbor negative feelings towards him at the beginning of their journey together, because she blames him (at least, her version of Loki) for giving her the powers that led to her timeline being destroyed. The events of the story could unfold as they do in the show because all of her character's actions and motivations would still make sense. However, the romance angle would now be greatly improved by these two characters sharing a past connection and, more importantly, not being the same person. The romance would have worked a lot better without that awkward element because the dynamic between the characters is interesting and Tom Hiddleston and Sophia Di Martino have great chemistry.
Obviously, the element of her comics backstory that involves her being a child, or at the very least a young adult, would have to be changed in order to make the romance work, but it's a small tweak that would have made sense in context, especially if she was snatched out of her timeline by the TVA. Marvel is usually pretty good about drawing from the comics, so it's strange that they only took a name and some of the power set from Sylvie's character in the comics. It's clear they wanted to tell a story about self-acceptance, which is why they went with the Loki variant angle, but they could have told a story that was just as emotionally impactful and interesting if they'd been less committed to Loki and Sylvie being the same person.
Loki is, overall, a well-done show that took a lot of interesting creative risks, and has the potential to change the entire future of the MCU. However, the Loki/Sylvie relationship was such a sticking point for some fans that it really took away from their enjoyment of the show. Changing Sylvie's character in these slight ways, and actually utilizing more of the backstory of her comic namesake, would have improved the story greatly, and added some more emotional depth to the dynamic between the two characters. Obviously, this solution doesn't adapt the comics version of Sylvie entirely accurately, but it's still a marked improvement from the direction they actually chose to take her character in the show.