Isn't it the other way around that if you use preferences, you tend to be biased, as you explained, ignoring this and that?! In fact, by judging objectively, we will be fair and not judge the story based on its appearance.
When I was still actively reviewing stories at NU, I judged stories based on the thematic/philosophical depth of the story, characterization, worldbuilding, and originality. I tended to ignore technical things like grammar (after all, the novels at SH are translations, judging grammar only touches the surface of the translation, not the content of the story). And I did enjoy that, I would even read hundreds of chapters (if available) before giving a rating.
And my preference was only an ethical limit on which stories I wanted to review, for example, because I like fantasy and SoL stories with family themes, then I would only limit myself to reviewing novels in that genres. I wouldn't force myself to review smut stories that I tend to avoid.
This way, I could enjoy the story (because I read stories that fit my preferences) while making a fairer assessment (based on the standards/dimensions of fiction).
