Yes! we can create several voice commands as you've mentioned.
Or we can create only one command called "auto scroll" and then you can say
- "stop" or "exit": for finishing the scrolling session
- "faster": for increasing the scrolling speed
- "slower": for decreasing the scrolling speed
The default speed would be 3 and it can be changed in a range of 1 to 10. Where 1 is the min speed and 10 the maximum. The selected number can be stored as the new default speed for the next time you want to auto scroll a page.