Lewis had greater variety and is also and ATG.
I agree that Lewis also deserves to be considered an all time great, but not that he had greater variety to his resume. Most of the men he fought were past prime versions of good fighters, or just not that great to begin with. What's more, he either lost or looked horribly unimpressive against Oliver Mccall, Hasim Rahman, a 36 year old Holyfield and a 35 year old Mercer. Holmes defeated a slightly past prime Norton, who was an all time great, and still a very good fighter in 1978. Earnie Shavers was pretty close to being at his best, and was possibly the hardest hitter in history. Cooney was a 25-0 prospect, who stood 6'7" during a time when most fighters didn't. Witherspoon, Berbick, Weaver and Smith were all young hopefuls who would soon go on to winning titles and having long successful careers. Mercer was a 30 year old Olympic gold medalist, coming off of the two best wins of his career against Tommy Morrison ( 28-0-0-24 ) and Francesco Damiani ( 27-0-0-23. ) Holmes at 42, showed incredible ring saavy and talent in totally shutting out mercer over 12 rounds. In 1996, a 30 year old Lewis fought a 34 year old Mercer, who hadn't won a meaningful bout in nearly 3 years, and some felt Lewis was given a gift decision!!!!
You'll have to excuse my bluntness, but there ain't no ****in' way Lennox Lewis had a better resume or career legacy than Larry Holmes.