Caravan traders could have rare items (unlootable). Not every one, but i.e. every 50th,.. . So instead of boring traveling on worldmap to locate bunker with gauss, you will be able to locate caravan trader and buy it. Or exchange it for another rare stuff with another player.
Rare items: gauss pistol, turboplasma rifle, bozar, mine, ... .
Because of new repair system and need of payment for that rare items, good karma with that trader, i think that it will not affect game balance.
The need to have enough money or stuff to trade with trade char will add risk. (current gauss pistol hunt is not risky). It will also eliminate creating of new alts only for gauss pistol hunting. Also players could group to protect rare item hunter, because wasteland is hard and you can find raiders etc..
Because of current gauss pistol map is nice, instead of gauss pistol, caravan traders could sell you map with location of that gauss pistol. Doors could be locked (or traped) and you would need another chars to break in => MMORPG?