There's a lot, actually. His biggest misdeed is still killing Han and that's all that casual viewers, who are huge majority, care about . they don't care about LST, his villagers, Finn recovered fine so Rey didn't bring that up but only Han's murder, and it was Hux who blew up Hosnian system not Kylo. You can blame Kylo for associating with that crowd but not for ordering the destruction, executing the destruction, giving a Nuremberg speech or even attending the rally (he was pointedly on his ship and not on SKB when Hux went full Hitler).
In TLJ, his master said that killing Han split Kylo's soul to the bone (means he regrets it) and then Kylo killed Snoke which is the most heroic takeout in ST so far. So that evens it out. he saved Rey, killed the big bad. Now, we are getting to the resistance part of the story. New Supreme Leader did not want to stop firing at the resistance but at the same time, resistance was the architect of its downfall due to incompetence of its leadership and their minions. so, again, that evens it out. they are at war. He deems them wrong. he keeps firing cause he can since they got themselves in that situation. That's all in the movie.
Finally, Crait. Luke's projection achieved 2 things: a) he doesn't have to kill Kylo and, more importantly, b) Kylo doesn't have to kill him (and add another major misdeed to his resume). So all Kylo did in TLJ is kill Snoke to save Rey (awesome), kill Praetorian Guards (awesome) and kill nameless Resistance redshirts (bad). oh yes, he made threats too (bad). I don't see how is this worse position than TFA where he killed Han and it wasn't clear whether he regretted it (TLJ clarified that he did).
So now we have TROS where Palpatine returns indicating that Supreme Kylo won't be our big bad. And that makes perfect sense. Palpatine was the big bad in 6 movies and ST would feel disconnected somewhat without him. so now he's back. In stories where there's a big bad above another, the lesser bad tends to redeem himself. from Johnny Lawrence to Vader to Mara Jade (wasn't she Palpy's protege?) etc, this pattern never failed.
as for his being given 2 opportunities, there are 3 movies. they are not gonna blow their load too early. it's the same reason why Force Bond was quasi-shut down at the end of TLJ. They need to open it in TROS in big fashion.
point being, his family wants him redeemed. His mother losing hope =/= wants the worst outcome for him. What makes movies satisfying is what satisfies characters in the movie and not few disgruntled fans. Kylo killed some fan's childhood hero and they want him dead. but that's not what childhood hero wants for his son and movie is written with his wishes in mind. And lets not forget that the biggest ST mystery is still how exactly Snoke turned Kylo. or was it Palaptine via a proxy? we don't know. we just know what caused the rift with Luke but not how he got turned. So that's a piece of a puzzle that will add up to redemption arc.