May not be what you’re looking for, but I rotate my canvas constantly and I use a shortcut modifier for it. Maybe you could try it out, it’s much less work and much more accurate than moving your entire arm down to a slider.
Just go to Settings → configure Krita → Canvas input settings → Rotate canvas
Then just set your preferred key + left click as ‘rotate mode’
Now all you have to do to rotate the canvas is to hold that key and drag anywhere on the canvas, and it’ll be like you’re rotating a piece of paper. When you let go of the key, you’ll be back to your brush so you can continue drawing. Much faster!