Lastly, only use "I" like that if you're being graded on an English paper. For everyday speech, use "me", or it will sound odd. Proper: "Tera and I went to the park." Natural (colloquial): "Me and Tera went to the park." (This is grammatically incorrect, but correct for normal speech.)

Also, it's impossible to be accurate with such a statement. Diligence is subjective and immeasurable. You can't really quantify it in concrete terms as to be able to say one person is "three times" more diligent than another, unless you're specifically talking about an outcome (you could say, "he accomplished more than three times the amount of work"). Instead, for an abstract term like "diligence", you should say, "He is more diligent than me." or, "He is much more diligent than me." You can also use other non-quantifiable words to express emphasis: "He is way more diligent than me."

They are not the same. "More than three times" = 4, 5, 6, etc times. "Three times" = 3 total times.

Almost the same. More than three times is MORE. EXAMPLE: 30 is MORE than three times 9 30 IS (exactly) three times 10. Same with words. Is he exactly three times as diligent? Or is he MORE than that? “MORE than three times as diligent”