Characters who, at different points in my life, I either disliked or outright hated but nowadays either am more neutral on, or even kind of like now. Either way, I don't hate them anymore. Remember, opinions can change over time. :)
Kind of found him rather dumb and annoying at first, but he's grown on me
Long my least favorite of the human Green Lanterns by far (yes, I like Hal Jordan more), I've gone from loathing Guy to just sort of tolerating him. While he's still my least favorite of the human GLs (again, I like Hal more however much people hate on him), I now no longer outright hate Guy, and its less "he's my least favorite because he sucks" and now more "he's my least favorite because the others are really cool and big favorites of mine".
Her extremely psychotic, foul-mouthed, abrasive personality takes a good bit of getting used to, but I think I eventually (sort of) did. I still don't want to romance her (Miranda and Shepard will always be my OTP), but I've learned to tolerate Jack more, instead of finding her plain unbearable.
Used to really dislike Kingpin as a Spider-Man villain, where he always felt overpowered and over-used to me, but I really do like him as a Daredevil villain and have grown to appreciate him as a generally well-written character. And of course, Vincent D'Onofrio's performance in the MCU stuff goes a long way towards winning me over also.
Still prefer him as a Daredevil villain though.
I used to consider her rather bland and boring, but I don't anymore.
This one's a bit more "complicated", in that there are still many versions of Lois Lane I dislike, but there are others I'm fine with. It basically comes down to how much substance, agency, and wit Lois has got Vs. how much of a useless damsel in distress she's portrayed as being.
I still think he's a Grade-A jerk, but I've nevertheless come to appreciate his role in the Marvel universe more than I used to. He's still far from a favorite of mine, but at least now I don't actively wish to see him get killed.
Mostly it was his Batman Begins version that helped win me over to this particular Batman villain, who I'd always found to be kind of annoyingly arrogant before. Nowadays, I like the Demon's Head about as much as most other Batman fans do.
Mainly, I felt that She-Hulk was yet another "opposite gender knock-off of pre-existing character", a trope I at the time rather disliked. But, after it was impressed upon me that She-Hulk is sufficiently distinct from her cousin and isn't "just" a Rule 63 Hulk, I conceded and let go of my hate for She-Hulk. I still don't love her, but I don't hate her anymore.
Took me a while, but I was eventually able to make a distinction between the 1990s era Superboy (who I still do hate), and later versions that I'm basically fine with.
