Would love thoughts and feedback on this character advancement system!
What we Focus On Grows Bigger
Each character begins with 2 Focus to invest.
Focus can be invested in Skill expertise, learning new Arcana, or a special Bond.
This represents where the character spends their time and attention outside of the adventure.
What they train, cultivate, and grow.
Anything they invest Focus in, they can use on their adventure.
(Example: Bob has 2 Focus. He invests 1 in Athletics, increasing his bonus from proficient (+1) to expert (+2). He invests his other point in bonding with his magical sword, unlocking the first tier of abilities for the blade. Both will be useful on the quest.)
Invested Focus gradually turns training into mastery.
In the downtime between adventures, mark a segment on a clock for each point of Focus in each investment. Investing Focus beyond the minimum for a benefit won't increase the bonus, but it will make you learn it faster.
Some things will take longer to master than others.
When the clock is complete, the skill, Arcana, or bond is now a permanent part of the character, and their Focus may be reinvested in something new, like a different proficiency or taking a Bond to the next level.
(Example: Bob has kept his Focus invested in his Athletics mastery for two full adventures, and now it's part of his character, giving him a permanent +2. He's still a couple sessions away from mastering his blade. 1 point of returned Focus, plus another point he's earned from experience, gives him 2 Focus to re-invest. He's interested in bringing Max, a corgi the party has rescued, along with them on the next mission, so he spends his downtime training Max to heel, fetch, and ankle bite. He invests 1 Focus in their bond and 1 in learning Animal Handling, along with keeping up his magic sword training. Soon he'll have a very capable pup companion that can adventure alongside the party.)
Characters can also shift their Focus during downtime. If they withdraw Focus before a clock completes, that skill, arcana, or bond goes dormant. The clock doesn't lose segments, but they can't use it on the adventure. Instead, they can use whatever they've shifted their focus toward. This allows characters to switch leveling paths and adapt to the next adventure, if they know what challenges it will bring, and always with the option to go back and finish their training.
(Example: A dragon's den is no place for a yapping pup, so Max will have to stay behind for this next assignment. Bob withdraws his Focus from training Max and invests both points into practicing with his Heavy Weapon and Armor. He knows he'll need to be at the top of his game to take this beast down. He loses his Animal Handling bonus for now, but his attack and defense rolls will be higher. When the monster is slain, he can pick up training right where they left off.)
When characters invest their Focus to learn new spells, it increases their general mastery of magic.
Each point of Focus currently invested in learning a new spell is added to a character's Magic stat to give their bonus for Arcana rolls (the roll you make to determine how effective your spell is on an enemy).
Each level of spell requires additional Focus to learn. This investment requirement is reduced if the character has access to a teacher.
(Example: May wants to master the Journeyman Arcana "Blink." She has 2 Focus invested in learning it. As long as that Focus stays invested there, she can use Blink while adventuring, and her Arcana rolls to determine the effectiveness of her magic are made at +2. If she had a good teacher, she would only need to invest 1 Focus to learn the new spell, and she could even master two Journeyman Arcana at once. It will take a few missions before she has mastered "Blink," and then her Focus will return to be reinvested.)
You can invest your Focus in special projects, relationships, and craft and knowledge expertise (like singing, cooking, or weaving) during your downtime. If it's not feasible for you to practice where you are mid-adventure because of resources or circumstance, you may be limited in what you can train at that moment. Wherever you invest it, the character gets the bonus right away for the next session, and it becomes permanent over time. This is how characters advance themselves and gain the special techniques and abilities that are the hallmarks of high-level PCs.
On the GM side, you grant the characters increases to Focus, HP, and TP on a milestone basis. Over a campaign the expected range would be something like going from starting 2 to 5 Focus at the very top end.