Steavsi Austinoi I'm trying to write The Doc this way; he's not any good at combat, just a fixture of the Denon underworld.
One thing I'm having him do is have him offer jobs, like an NPC quest-giver, when he runs into situations he can't handle himself. I'm running two threads like this right now, Back Alley Exorcism and Mile-High Hack, in which the Doc has hired people to take on threats beyond his capabilities while he helps from the sidelines. For a farmer, that might mean hiring mercs or bounty hunters to protect his crops from bandits, or to recover something that he needs for his farm. I'm also just throwing him into social threads wherever he would fit.
The other way I'm hoping to integrate the Doc, who is a pretty skilled street medic, is to have him provide medical care and cybernetic augmentations for other PCs - and meet them that way. I will probably advertise in LFG to see if there are people interested in writing those kinds of stories. For your farmer, it's probably his starship-repair skills that would be in demand.
I also have the Doc in a faction, Darkwire, that tells stories in the region where he's settled down (Denon), and I throw him into those stories in non-combat roles whenever I can. That starts building character connections for more stories.
I've only just started writing him, so I don't know how it will go, but here's hoping!