Yes with pleasure!
At the moment you can use the AS5147_SPI which has the same parameters. But you’re right that it is confusing!
You are absolutely right. But adding an additional timer will make very complicated Arduino code. I would make initial simple support and if people are not happy with it we can always make it better.
The same is true for MagneticSensorAnalog which is not optimal in any way 
This whole library is somehow more meant to enable then to optimize