Wow, That's two really great shouts. Beterbiev vs Briedis would be amazing, I'd probably favor Briedis heavily but would definitely be a good scrap. That's a fight I never thought about.
Babic vs Kownacki - low level HWs with no defence and that throw a very high volume of punches would make it a very entertaining fight while it lasts.
Roberto Duran vs Julio Cesar Chavez Snr and Marvelous Marvin Hagler vs The Real Deal Evander Holyfield.
Makabu Vs Goulamirian unification, it needs to be made. It'll be a right tear-up as long as it lasts.
My understanding was the premize is that you could match fighters up and down from any weights in this fantasy match up hence choice of Hagler vs Holyfield 2 great warriors with excellent boxing ability, heart, Will desire, durability etc. Marvin could have fought at Super Middleweight easily and Evander at Light heavyweight. Do you feel the gap in weight to much?
The OP said up or down "A division". Hagler and Holy were never separated by a single division. Ask your uncle to teach you how to read and comprehend better...
Conor Benn Vs Eubank Jr would probably be a pretty good tear up, my money would be on Eubank jr., although I personally like Benn more.