An argument could be made for Holyfield! Yes, he's the greatest Cruiser of all time, but he moved up to HW & became champion of the world & there's no bigger prize in sport, so he was definitely more successful as he moved up!
On the contrary. Tommy was a menacing KO machine at 147 - 154. He was still a very good boxer at 160 and above, but at 147 - 154, he would have never lost to a fighter of Barkley's caliber.
While there is certainly more prestige at HW, Holyfield was a better fighter at cruiser. Who in history would be favored to beat Holyfield at cruiser? How many fighters actually beat Holyfield at HW? Against Bowe and Lewis, Holyfield won one out of five. Holyfield's record at HW is impressive in terms of whom he fought, but he was rarely ever dominant.
Agreed. Holyfield could have stayed at Cruiserweight and dominated for ten years, in my opinion. I can't think of one Cruiserweight that I think would've likely beaten him from the time he left to at least a decade after. He was perfectly sized for CW. But no guts, no glory. The glory was in the HW division. Holy is a gutsy man.