I do not think wholesale reform to everything is a good idea, because there will be a whole mess as teachers try to find their footing. We need to debug those and test and adjust and get comfortable with it.
So maybe two or three major reforms at most get implemented over the course of a year.
I think we can staple a "Leaf University" on top of the existing educational system before anything else, really.
New Genin are required to attend for a semester before doing field missions and after that they rotate between training/taking classes and field missions on a trimester basis.
Initially we'll have a small class of civilians that are only there to learn medical stuff, sealing theory or useful stuff like that but we can expend things as we get more infrastructure.
If we coordinate well and make a large portion of the courses very practically useful (training, jutsu development, tactics, field and practical exercises etc) this can potentially reduce fatality rates by a large amount due to better trained soldiers.
We can make things flexible and remove a lot of the useless bulk that someone might typically associate with "university" courses. You can have a decent course take like 6 weeks if it meets every day or so and is meant to impart practical knowledge.
The above of course doesn't apply to Sealing or Medicine because those are serious business (and no way in hell is Hazou going to speak about how to teach the later efficiently).
Likely part of the notes is what Jiraiya knew by experiencing infusion or by experiments. And the notes only partly reduce the difficulty.
I feel like you're making an assumption on how important actual sealing experience is. If it works like Arcane Chakrapunk Computer Science like we think it does, then its a moot point.
There
are styles in things that may seem super formulaic like proof writing or writing code. But a for loop is a for loop, a proof by induction is just that, and
there wouldn't be common names for Sealing crap like a "Fujikawa node" or whatever Sealing gibberish Kagome spouts if these
weren't generalizable things you can use in many scenarios because "This is how they interact with the rest of the seal to do what you want."