Penetration is the more important thing.
But 16” or so of penetration is probably plenty.
So, if you have two loads that both achieve excellent penetration, then the better load would be the one that expands the most.
These considerations matter the most when one is contemplating the less powerful chamberings; .380 Auto, .38 Spl. and .32 Auto.
With these chamberings, the most important thing is to first achieve adequate penetration.
IMO, as a general proposition, people make a little bit too much out of expansion anyway, because you do not control this. There are many factors that affect the terminal performance of bullets; clothing layers, whether or not the bullet strikes bone, the angle of entry, distance, barrel length, etc.
Regardless of what you decide, for me, I always remind myself that there are only three things that are directly under my control.
1) Caliber; the diameter of the bullet when it leaves the barrel
2) Muzzle velocity; the speed of the bullet as it exits the barrel
3) Bullet weight; the weight of the bullet when it leaves the barrel (may NOT be the same after it strikes its target!)
Everything else is a variable to one extent or another.
Shot placement matters!!!!!!!