Basically what it says on the tin: make the bonuses for the artisan lines, blacksmith lines and pasture line global like the ones from tech or the date clan trait instead of only affecting units recruited in that province. This should make the business of recruiting troops (specially higher tier ones) less annoying as you'd be free to make recruiting provinces away from the specific provinces giving the bonus, it would also sidestep the whole "my bow warrior monks are worse than the ones I can recruit now that I got a master fletcher".

There's already a mod going for something similar in the workshop:
https://steamcommunity.com/sharedfil...?id=1781270424

That mod is a much bigger departure from vanilla than what I'd hope for however, and just rolling back the individual buildings to be in line with the vanilla ones would face the ridiculousness of a faction with 2 master armourers getting yari ashigaru with the armor of unupgraded naginata samurai or one with two master bowmakers having bow ashigaru with more accuracy than unupgraded bow warrior monks.

The way I'd see it work would be to remove the bonus from the buildings entirely and make it into separate clan buffs like "Inspired Endeavors" or the likes, you'd get them through an event on getting the building and loose them through a separate event popping when you no longer have at least one of said building or you got a better version. This would make for 12 separate buffs of which you'd only have a maximum of 4 at the same time (since there'd be 3 versions of the same modifier at different building levels). Making them into a single thing with multiple versions would look neater but also require an absurd amount of variations.

I don't think making the economic bonuses global would be a good idea since it'd severely impact the economy of the game and might end up with the AI spamming veritable avalanches of troops, navies and castles.

I'm not against making it myself, but I'm trying to learn how to and it looks a wee bit daunting so any tip is appreciated.