My only confusion is why the king calls the knights and servants "dear" or "darling" I've made all my romance options he/him I am not sure if this is on purpose or there is a confusion due to the change in pronouns
It is very much on purpose. King Arthur uses terms of endearment very often in his speech, regardless of the person he is talking to. It is just part of his character.
I don't hate it, myself. I do hope that eventually he'll have a more personal endearment for our MC if we're romancing him...such as love or my love. <3