Priestess being denied the promotion very likely is due to the Rank gap, although if they had someone from the Guild accompany them on a quest or two that interpretation would likely change.

Also Goblin Slayer being that guy at the guild never gets old. Also is a beautiful showcase of the difference between the adventurers who get what their job is and those who don't. The guys only chasing glory look down on him while those doing the job, at least in part, to keep people safe value him because he is probably the most efficient means of reducing the goblin threat. Which has 2 major results those types of adventurers really like. 1) less rookies die to unreasonably large Goblin Nests because Goblin Slayer usually takes care of them before they become a problem. 2) Since the more difficult Goblin extermination Quests get taken by a single dude it frees up the more skilled generalist Adventurers for other dangerous beast in need of killing. Win-Win as far as they are concerned. Shame the glory seekers just don't get what kind of value a specialized pest exterminator brings all of them.