I feel like I've pretty much limited myself to 2-3 weapons so far. I'm specced for small guns, and I run with a combat shotgun, hunting rifle, and an SMG for when I'm low on other ammo types. I very rarely switch to other stuff, and I find enough hunting rifles and combat shotguns to keep mine repaired.
I was playing it like Diablo, and like I had OCD. I would start heading toward my objective and try to explore as much as possible, and always find a "dungeon" (building, cave, subway system, etc). I would thoroughly clear that, end up with full inventory, then go back to Megaton to sell and repair. Then I would continue. I would take me forever to get to any objective. When I get back into it again, I'm gonna try to be a little less OCD about the way I play, otherwise I'll get bored before I get anything significant done.