Stall speed

It depends on your gear,driving habits, among other things.
If you have a football field sized torque curve stall is less important unless you are drag racing. Then shift recovery plays a role.
A small engine with lower torque at lower rpms will want/need more stall to keep the cam from falling below its operating range.
There are compromises to everything. Big block torque makes the wrong converter a little more forgiving IMO.
You can also have too much stall but that is another topic.