At the moment..
2 octave scales over 4 strings
Major, melodic minor, harmonic minor and modes thereof.
Chords of each scale type, then with upper triads (1,3,5,7, 9, 11, 13)
If nothing I have to learn, then choose a standard jazz tune. Melody, walking bass, soloing.
Maybe some repetitive exercises in front of the telly.
It makes Back in Black a piece of p@ss.