UNIRONICALLY? I was kind of thinking this. But the way I view it, he's sort of an.... alternate timeline rose? I think of him like I think of Radiance- both are representations of paths Rose *could* take- if she didn't have a support network of friends.
Well, actually, to explain what I actually mean, I veiw the Chronicler as an extra-dimentional being. He, quote, "exists outside the world- among the stars" and that's also how he can tell vaugly how certain things will go- the movement of the heavens and the occasional whisper of the all-watching stars (p.s the themes of observation vs obscurity in this series rules). He's a Chronicler yeah, but he implies that long ago, he used to be a normal man, a normal man who looked at the stars and fell madly in love. So madly in love, that he left his shadow behind and leapt into the constellations.
My "he's a version of Rose" or at least "he symbolically resembles rose/reflects a part of her/is a path she could take" comes from a few things.
1- Obviously, his appearance. Is very "sus" as the kids say- a right leg that is somehow damaged, snow white hair, purple eyes- and the fact that he is mostly dressed in oranges, golds, and blues, just like Rose and Lily. And of course, the bouquet of purple and blue roses.
2- The parallels. He and Rose both have a thirst for knowledge- but unlike her, he no longer hides behind a shield. He implies that he used to "be a lot like her"- and that he was afraid of the light and power because it would take him away from his family and the world. However, he still is a lot like her, in the way that he is very detached. Rose, again, appears very apathetic- which, like most other things, is another shield/defense mechanism. Unlike her though, he genuinely seems to not care about people who aren't Rose- he goes "hmm? Lily? Well [s]he'll be safe too, of course of course." Not that he's cruel- he's just detached
3- He seems like a person she would not want to become. Though he doesn't seem malicious, she refuses a lot of his offers and help and only asks for what she will need to save her friends. He seems mildly surprised by this- which is strange- but then he shurgs and obliges, pausing only to scribble something in his book.
4- Speaking of, this ties back into both the Radiance & Rose parallel- Radiance and the Chronicler are very very similar in some places. They both became something different due to light magic. They both seek knowledge. They both have pale white pupils. Radiance's meeting room and the Chronicler's tower have one thing in common- though Radiance's room is pure white and the Chronicler's is messy and colorful- *neither of them seem to have any shadows at all.* Both seem to chase away darkness and obscurity- the difference is that the Chronicler isn't evil, just apathetic.
Tl,dr- I think sort of like the Crow, Rowan, and the Rose of Ice itself, the Chronicler is another metaphor for..... something. Personally, I think he represents Rose's secret thoughts about what would happen if, she too, embraced light magic and left her friends. But she won't- she will turn away and walk back into the comforting shadow hand and hand with Kivan and Lily.