I have used the quotation commas because some of them would not be heavies today. My list would be . Langford Fitzsimmons Choynski Maher Sullivan Goddard Jeffries Willard Sharkey Somewhere along those lines. Who would be your picks?
Those are the ones that immediately come to mind with the inclusion of Sam McVea. Kudos for including Goddard. He could whack.
In addition to the names you have mentioned, you could make a case for Frank Herald, Sam McVea, and Gunboat Smith.
Herald seems to have been the Ernie Shavers of his era. People said that he punched harder than Sullivan, but presumably Sullivan was a better finisher, and took a punch much better.
Some might have had more raw power, but in terms of lethality, I'd say Sullivan and Fitzsimmons, Sully being harder to rate. I don't think Dempsey necessarily hit harder than some of th guys before.