Victor Von Doom is of Romany blood, yes. However, his depiction in the comics shows him as mixed blood, not full Romani. He is supremely self-confident, even arrogant, but in many ways, he could be summed up as "A smarter Tony Stark turned villain and 'despot.'" Doom created an armor that can give Iron Man a good challenge, but without the two things Stark needed to make his so powerful, the Arc Reactor, and Stark's control system, neuro-mimetic telepresence. Doom's armor is controlled by micro-switches, and yet, it challenges many heroes. Doom is a leader by conquest, and honors his family by identifying as Doom. He has honor that many other villains may lack, and a skill in turning abstract ideas into reality with minimal resources.

I think RDJ can actually pull it off