Suspect what works is very individual and goal dependent like Square says above. For example, my main goal for the next year or so is to get enjoyment playing solos alone at my drum kit with no backing of any sort.
And like Uncle Larry indicated earlier, for me it means doing whatever I feel like doing.
Typically:
1. Free improvising solos, which seems to be the key to my improvement as a drummer and a musician. This is how I spend most of my practice time and where both technique and musicality is developed.
2. Spending a small amount of time reading and playing, as musically as possible, the technique exercises from the classic basic instruction books. This is where basic reading skills are developed which of course is useful for studying musical ideas and collaborating with others.
3. Spending an even smaller quantity of time working through style books such as John Riley's jazz books, Gil Sharone's Jamaican book, and Stanton Moore's Groove Alchemy. This is where perspectives on other people's creativity are studied, genre conventions practised, and reading skills furthered.