Cam shaft suggestions
I'll just echo what's been said by the previous posters...very sound advise.
Low end power can be very suggestive and with your ''stockish combo'' it's never gonna be a tire blazer imo even though it's not a real heavy truck, thou 318WR may disagree :). I suspect the cranking compression will be fairly low...125/135 ish psi, so once that's known you'll be able to justify if a cam upgrade will be a good cost per dollar endeavor.
That said, get as much timing in it as it will take on the fuel you run and find out what rear gear you have and how tall your tires are. That may have more to do with the performance then any cam swap could bring. The Magnum teen 6' bed i had wouldn't have been anything to right home about except for the low gear 5spd, 3.55's & smallish 29'' tires.