I don't think Ronnie would be any bigger compared to Arnold in his prime. How many pros have a 22 1/2" arm, 58 inch chest and a waist as small as he did? NONE. All the pros now have bloated roid gut from GH, including Dorian, Flex, Ronnie. He was kicking everybodies ass today, 25 years ago.
I think that Ronnie could play a Terminator type role, kind of like Robert Patrick did, meaning only minimal speaking parts, intentionally sounding like a machine.