It's a great idea, but sadly it's not taleworthy. Keep in mind, this is Mount and Blade, not Anvil and Hammer. More specifically, this isn't World of Warcraft. Although expanding the scope of jobs you can do carries merit, it's not worth expanding on in my opinion.
It would be a massive effort on the developers part, for a system that would be used only so early in the game. As you progress into a successful mercenary within a few months, these minor tasks ( Blacksmith, Fisher, Woodsman, Farmer.. etc) become irrelevant and don't provide for your growing war machine.
This can be paralleled with selling low quality loot, raiding peasant groups and doing courtier jobs in the beginning of the game. At first, you need the money, but you eventually grow out of it.
On the other hand, Guilds would be a nice addition to the game. I like what the devs did with enterprises and expansion on that would be nice. Possibly different skilled trades (masonry, smithing, merchant) groups would offer bonuses to your character if use properly (upgrading walls/emplacements, forging special weaponry, trade routes/trade missions). It would be hard work, but it would progress with the player the entirety of the game, and help them fund their empire in ways other than simple killing.
