So as to keep this project a game instead of an obsession I bring in the die (dice) and kitchen timer.
The timer is for measuring off intervals, naturally. For everyone there must be an optimum amount of time to engage on an activity. It may be as little as 10 minutes. Or it may be as much as 90 minutes.
Bringing in a dice introduces a random factor.
Let's say I roll it twice. Then there are 36 possible permutations. I can divide these up between mu languages: 15 for Japanese, 10 for Dutch, 5 for German, and 6 'free' rolls that allow me to do what I want, or to start another language.
Furthermore, I can divvy up the 15 Japanese throws to the different activities I've chosen to do: say 5 for kanji, 3 for sentences, 2 each for lJrE, lErJ, and lJrJ etc.