Alright, so here goes: 

-For my character, I've had in mind a burly "settlement builder". Basically my character belongs to one of the more established settlements in the Wasteland(can come up with name later) and is tasked with scouting out potential areas for outposts, major settlements and resources. He's also tasked with clearing the areas that are worthwhile, which includes killing raiders and bashing ghouls to bits. He's been in this position for two years and before that served in the settlement's militia. 

-In terms of plot, we could go with the arc of unifying all settlements under one government. That could introduce a number of groups that would oppose, would support, maybe ending up in a multi faction war in the vein of New Vegas? 

-We could also try to explore groups or cults that are kidnapping settlers for their own ends, effectively depopulating the wasteland. As I typed that it sounded crappy, but if you feel like it has promise, let me know xD