The only way you can get budgets for movies about this kind of thing is to include some nonsense to attract non motorsport fans, it's a harder sell otherwise. it depends what they want to do really? You can make movies about motorsport and make them about individuals and make them very good, the Dunlop bike dynasty one is excellent, the Faster series are too. But did they make a bunch at cinemas? not sure.
But the Hunt/Lauda one was bang on because it focused on rivalry and two amazingly contrasting people, and also a period that everyone remembers.
The only movie I think left is a Prost/Senna one. That shows BOTH sides, not one utterly biased and rather pathetically biased one with blokes who worshipped him brought in as so called experts. there needs to be a movie about that period for me. That rivals Hunt/Lauda even more doesn't it? Senna appealed to non race fans as it showed the side of him that WE all knew about but non fans did not, The intensity, the worship and almost unsettling belief in himself and God, the childlikeness, and the desire.
There is a Sheene movie coming, that is an obvious choice, and for me the early 90's Rainey/Schwantz might get close. But unlikely.
Ronnie was a talent, and his story was great, but it isn't in the same league as the ones mentioned above in terms of its ability to sell a story to wide audience.