Hey @donbonbon
I hear you, quaternions are confusing at first. I think the more you work in them the anxiety of that extra curve will subside and you’ll learn how to work with the curves instead of fight them.
The first thing you should do is understand what quaternions are and how they work. For that I recommend Nathan Vegdahl’s Humane Rigging videos. He has a terrific chapter all about these rotations. He even goes into how you would go about animating with them. https://youtu.be/FRD0PgsY3pU
Once you understand how they work, most the battle is done. Working with them in the Graph editor becomes more about adjusting your spacing rather than, moving around a value randomly and seeing what it does.
I definitely recommend your number one work solution. Create a break down that is defining your ease out movement. This is super common in a lot of workflows, even in euler rotations. The reason being exactly as you said, it gives you the most control over your performance and as an animator that’s huge.
So put a breakdown 4-6 frames from your keypose and see what values are changing in the graph editor and tweak those curves to get the exact spacing that you want.
I hope this helps you out. Keep at it!
