The Real Madrid star has evolved from wiry winger to powerful forward since leaving Old Trafford for the Spanish capital in 2009 and has gone onto score 395 goals for Los Blancos.
Neville, who enjoyed a six-year spell at United with Ronaldo, believes there is more to come from the 32-year-old as he enters the latter stages of his career.
"I was thinking the other day, what's the long game for him? And I wonder if he's going to go on and play into his 40s," Neville said on Sky Sports' Revista de La Liga. "I wonder if he's building up for a long career as a centre-forward, where he can still score two goals and live off moments.
"He's living off moments more than his all-round performance now.
"Since he's gone to Real Madrid he's contributed enormously to everything they've done but he's living more off moments rather than a contribution through a whole 90 minutes.
"He'll be thinking Pele. Those numbers. Those scandalous numbers you think you can never achieve, the appearances, the goals, and that to me is where it's going. I think he'll play for longer than Lionel Messi, I think he'll score more goals in the end and will go on to do incredible things.
"I think he'll go on for a long, long time. And in this game, he's becoming a goal-scorer, he's getting in the box more, he's coming across the near post, his heading is incredible anyway.
"I think we've seen the transformation of a player. We've seen Ryan Giggs go from a flying winger to someone who played more centrally as a midfielder. We're seeing Cristiano now as a centre-forward.
"He knows he can't go up and down all the time now. He knows he can't go past players all the time. He'll become a goalscorer, a poacher and a good one."