I think it's a mistake to think its the priest primary job to rez. With rez being tied to first aid, its everyones job. And I still think priest is not OP because it can't do everything at once.

The strengths of BC is also in the buffs (and wide damage types), which really have been ignored in this thread. Skin make a huge difference. Before priest, the common healer setup was psych/mentalism. But the content was actually tuned easier. Group size shrank from like... 9? and elite mobs did not lock. People would zerg druid events, manticores and labs.

Priest being added was to be greeted with tweaking content that requires a tank. The idea was, there were to few tanks to make things hard, and once priest happens a switch will be flipped and stuff will be harder. I don't feel like finding the post but it was said by Citan, and i don't know if that 'switch' was crits or not. Around the time priest dropped AoE damage no longer scaled and probably 2 months after crits were added.

I do understand your argument that priest makes the other options seem lame. The skillset that I think should get attention to become more support-y should be bard/horn. I think it's the easiest to balance because it requires hands, and honestly I want the bard class to move away from the 'get hit do more' play style it currently has, which is a bit solo friendly for a group class.