I don't think many people liked Joyce prior to season 5, she was typically a nag. But that storyline was done so well that even if you don't care about her you feel for Buffy and Dawn (and the rest) who are going through all of it. So yeah, I think a lot of it is more about the gang than Joyce herself. I mean even the episode focused more on how the death impacted everyone.
On the other hand she does have some awesome moments throughout the series, like any time she interacts with Spike (including hitting him on the head with an axe)
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"Hope is allowed to be stupid, unwise, and naive." ~Sir Chris