Split the current general practice into 3 separate units
Since the general practice always advances with the learning it is hard to go back and work on earlier material ( for focused/intensive practice). So my suggestion is to split the general practice into 3 parts to correspond to the 3 sections in the learning tree. Then if you pick the first practice it will focus on whatever you have achieved up to the end of the first section and the same for the other two. This allows you to focus on sections. Naturally this means that the 2nd practice will include lessons from the beginning as well, and the 3rd section will be as the present practice is now. This would also make it better for doing speed practice, because you can work on speed in an earlier section and take more time in a later section.