So I remember Jojolion teasing that there was more to Speed King's power than just raising heat, and that nobody knew the full extent of its capabilities. In the end, this just turned out to be the additional ability to store heat as landmines, but my imagination has run a bit since then.
What if the stand's name alluded to the true nature of its power? It's typical of Jojo to reveal stand abilities in misleading ways, because they're introduced being utilized in a specific, creative manner that doesn't make its nature seem obvious at first glance. So what if Speed King was like that, as I speculated?
It doesn't have the power to heat things up, so much as... Speed King accelerates motion it interacts with; Like Made in Heaven but on a much smaller scale, and capable of affecting living beings. In this case, Speed King is using its power to accelerate the vibration of molecules, which is what generates heat; Thereby increasing the temperature.
That's the secret to Speed King's power; Heat is just an extension of that ability, a creative application. And there's a lot of other ways Jobin could exploit this power; He has some fancy cars, after all. He could speed up biological processes to mess with your blood flow, or make thrown objects faster than bullets. Falling rain droplets become piercing under the power of Speed King. Maybe this acceleration could even affect time itself... You could parallel this with Josuke discovering how his bubbles really work to unlock Go Beyond’s potential.
