Barnett, Sergei, Aleksandr, Werdum, Herring, Mark Hunt could never make 205. Maybe Fedor, Nog and Cro Cop could have. We only know for sure Coleman and Randleman were able to make 205. Overeem fought at 205 and HW in PRIDE but after PRIDE was bought out he started getting really big and definitely reached a point to where 205 would be impossible.
UFC has had some good heavyweights but never had a division as deep and talented as PRIDE.
Cro Cop had 1000x better takedown defense and submission defense than Cyril Gane.
Nog was a very good boxer and took down almost everyone he ever fought.
Go watch both Nog vs Barnett fights or Nog vs Herring 1 or Nog vs Sergei if you want to see well rounded heavyweights.