Roy jones won the HW title @ 190lbs.
Sure Tunney in theory isnt Rjj, and Ruiz wasnt the best of his era, but it should factor in:If Tunney was ahead of his time then, same for today.
Even Floyd Patterson was considered small for his day, but if there is an example of a small man hanging with the best, I feel Tunney would've been that example over Patterson as well as Marciano. All threee didnt weigh much, but I think...Tunney would have the most success in any era as a small HW.