Fralins are great, but have perhaps a more modern take on the vintage tone. Maybe more open, with some extra high mids. I like it with flats and nickel rounds, but I sometimes want to try something like SD SPB-1... I'm also liking Model Ps on another bass, and I like them for a more modern rounds tone. Great, inexpensive pups for a little more oomph. SPB is also inexpensive, as is Wilde (Bill Lawrence) P46 which I've heard is similar to Fralins in how clear it sounds.
But in the end, strings and setup do wonders. Perhaps set the current pickup a little lower?