The futurists were a funky group, I'd be interested in this just for
their effects on Italian food alone. Death penalty for preparing pasta, anyone?
To fulfill the challenge, maybe Musso just becomes a straight-up futurist rather than forming his own ideology - his views changed a lot around the time of WWI anyways, so it isn't too far-fetched. He'd still have the charisma and nationalism to win him popular appeal, and he'd still have the glorification of progress and violence, but his social policies would be very different.
I'd see a Futurist Italy as more totalitarian and more prone to the weird excesses that are a staple of modern dictatorships. Rather than calling back to Rome, Mussolini's dictatorship might have an almost sci-fi aesthetic to it. Maybe there'd be a concerted attempt to develop a "New Man" through total social indoctrination.