Sure sounds cool! Maybe advanced processing techniques could be introduced to combine the different fuels (slow cheetah and x makes an extremely large capacity fuel cell, maybe introduce liquid byproducts to introduce complexity so it isn't over powered. Could add a distillation process to convert from fast fuel to a slow burn or vice versa).
There's a lot of ways one could go! You could add an optional dependency to your mod for Cheetah ores, this indicates to players that your mod has extra functionality with this one, and gurantees in each data stage (initial, update, and final fixes) that your code will always run after Cheetah ore code, very useful. Also you would have complete creative control, wouldn't require any code on my end.
Let me know if you'll need any changes on my end, happy to accommodate. Pm me on the Factorio forums if you want to further brainstorm intercompatibility.
As for RSO, I'll get the process started with Orzelek! (If you're curious, you create a RSO resource config, supply to Orzelek, then they go on to release new version with latest mod support.)