While personally, I think this is a entirely legitimate direction to take with the story, I'll point out that on some level those 90 chapters of relevance can exist for the purpose of heightening the impact of the character's removal.

It's entirely possible to deliberately write a female character who exists purely for her death to motivate a male character (or vice versa, but it's likely that fewer people would complain,) who's well developed and active in the story for a long time, if the author is doing so simply to set up the extent of the motivation. And I think some people are concerned that, given that Eliezer planned Hermione's death from the very beginning, this is just what he did.