There's lots to like about this story, like the ridiculous number of blatant pop-culture references and fourth-wall breaks, and Latte's embrace of her role as a spectator. That said, while the story does some neat deconstruction of romance novels, it's also incredibly meandering. In addition, it falls prey to some of the very flaws it makes fun of, and I ultimately wasn't impressed with the conclusion of the story. Also, while the 30-chapter epilogue was okay, the 9-chapter side story felt pretty pointless.
Anyway, regarding these flaws. Firstly, Ibelin:
Ibelin never receives sufficient characterisation or character growth. That's the whole point of the main story, but the execution still feels weird; and it makes little sense for the story to blame Ibelin for being a bad friend to Latte, when Latte was no different to Ibelin; neither tried to understand the other.
Finally, Latte helped multiple other characters grow, but somehow didn't do so for Ibelin, even though the epilogue would've been the perfect place to do so. Instead, we're left with her remaining a disappointing non-character, which leaves a glaring hole in the otherwise pretty self-aware story.
Secondly, Arwin:
As is common in such stories, the bad boy is the love interest. In my eyes, the story never managed to sufficiently reconcile the teasing bad boy from the mass murdering bad boy. For instance, I was put off when a villainess attempted to murder Latte, and Arwin retaliated not just by killing her, but by putting her in an eternal torture scenario. And at other occasions, Arwin playfully suggests to Latte that he'll destroy the world if she comes to harm, which is not actually romantic once you think about it.
Finally, regarding the notion of undeserved protagonist bonuses:
The story criticizes Ibelin for getting things handed to her as the passive protagonist, but Latte spends most of the story trying to be the passive spectator and nonetheless gets thrown into the protagonist limelight, including getting attention of all the love interests.