So, from about 5th fret (or where it would be should there be frets

) upwards I'm able to comfortably do a cello-like vibrato where the whole arm moves. Lower than that and it feels my options are:
1) vibrato from the hand/wrist, feels smooth, painless and natural per se, but I have trouble coming up with a satisfying tone
2) try lifting my elbow higher away from the body, the problem is it tends to lock my arm even more
It feels plausible that woodshedding with option 1) could, with time, yield an even tone across the instument's range. But 2) or some other option to avoid radically different technique in a low position would intuitively be a more natural goal.
What's you guys' approach on this?
I wear the bass reasonably high, the end of the fingerboard is about at my navel. Not taking lessons at the moment as it's not quite compatible with my present schedule or wallet.