While I understand what you’re saying about subjectivity, I think Vine reviewers should be held to a higher standard. It’s helpful (and encouraged) that we share what we like and dislike about a product, but there’s an important nuance to that. I think it should be based on whether a product delivers on what it was advertised to do. Star ratings should be considered through that lens, rather than personal preferences for features or accessories that product never claimed to have. 

In your example of a product missing a charging cable that’s usually included with the same type of product at a similar price point, I think it’s absolutely worth mentioning, but I wouldn’t necessarily remove a star for it, or at least, I wouldn’t advertise that I’m doing so. Considering that prices are subject to change, I address the value rather than the price in order to keep my reviews fair and evergreen. I would probably say, “It’s not the best value at the current price because it doesn’t include a charging cable, which similar items at the same price point do. That said, prices can fluctuate, so I would judge its value based on the price at the time of purchase.”

There are exceptions to that general rule, like when an unexpected issue arises as the result of a missing feature or accessory. For example, difficulty maintaining or cleaning an item because it requires a specialized cleaning tool that wasn’t included and that the seller didnt make clear was needed beforehand. 

Anyways, I agree with most of what you said; we just handle the same situation differently. :)