Having dealt with some hand problems lately which lead me to several specialists in the field of musical performance injuries, I believe there IS an ideal position for the bass. Predictably, it's "not too low, not too high."
When I went in first they had me put my bass on and play some, and they immediately pointed out that I had it much too high. Playing the bass high improves fret accessibility, but it comes at the expense of healthy playing form. Your fretting hand elbow must bend at a sharper angle, which puts more stress and stretch on your ulnar nerve at your elbow which can manifest itself in many of the problems often thought to be rooted in the wrist (tingling and numbness in the fingers, hand pain). It also encourages awkward wrist angles in the plucking hand unless you bring that elbow far forward, which puts more strain on the shoulder.
Playing the bass too low leads to improper fretting hand technique in that it forces to angle your wrist at an extreme angle in order to fret notes. (I think the problems with this style are more obvious and known to most here so I won't go in to it).
Essentially, you want to play at the height that imposes the least angle on ALL joints involved in playing the bass. The elbows should be relaxed and open, wrists should be straight, and the fingers should be nicely arched. This has nothing to do with looking good or the genre you're trying to play, and everything to do with keeping your body as healthy as you can for as long as possible.
