Most players play on 1 spot for most of the time. I only play above the bridge pickup. Not because of the sound, but because of the tension there is on the string.
To me, it is the player not the string, not the scale of the bass, not the instrument that wasn't design for it nor the cab that can't handle it.
Ok sure the cab and amp need to have enough power but outside of that, I found that the B string need a different approach to make it works. Like plucking it less agressively closer to the bridge than the other strings. No on ever tried this exercice :
Play the B string closest to the bridge
Play the E string a little further, maybe over the bridge pickup
Play the A string in between your pickup
Play the D string over the neck pickup
Play the G string just in front of the neck
Play the C string over the 24th fret
This is a way to even out the sound of each string. try this, then play all your string right between your pickup. Listen very carfully how each string sound with the other.