I would add the word "He" there to tell us who lacked rest The doctor said my father was fine but that he lacked rest."

I personally think you just need to add "A" before Career and Job "A" Career provides more happiness in life than one's social life I believe "A" job has more effect on one's happiness than a social life. But in the flow of this particular sentence, you want to keep using the same pronoun "One's". ONE's Career provides more happiness than ONE"S social life

I think "Bloom" is more directly connected to flowers "Blossom refers to anything showing growth

"I've always lived in dread of this moment"