I've found with myself and students, is, less is easier to understand and "retain". Making it useful is more important.

The best jam tracks is simply turn on the radio. Don't be particular of the station. Talk radio can be fun if you're writing. (write the 1st paragraph of a newspaper story, and try not to make it boring or as disjointed as most 1st paragraphs)

I hate this excercise, but learn chord scales. You will be shocked as to how pentatonic they are and extremely enlightening. (maj7 to 7th triadic)(there's tons of info with this logic...and reasonably simple.)

Many of the items "notice" is saying are very important. Play any scale without a pick or fingers. You'll be markedly suprised at what the right hand does naturally. (if you're left handed...) After the left hand "gets it",
the right hand can be a bit,... more entertaining. Some work, nonetheless.