Yeah, if only there were some book coming out with ideas on organizations sponsor an adventurer. Call it a "patron" or some such.
As far as the rest, that's what sidekicks, hirelings and connections developed through play are for. Basically I wouldn't want one PC (or PC class) to get anything powerful enough to matter that wasn't resolved through actions of the character in game.
It's not the worst idea in the world, reminds me of old 2E games where fighters got retainers and so on. But just like those retainers, it could be a lot of overhead. Fun in a way, but not sure we need a whole set of rules customized to specific niches.