When fielding a ground ball should you get the ball out of your glove as fast as possible or should you keep the ball in you glove until you get the four seam grip, setting your feet during that time?

on a ground ball you want the ball out of your glove below your knees.

It depends on what type of GB:

routine GB right at you - I teach to funnel to the belly button while getting the feet set and throw.

forehand - throwing hand meets glove in middle of body and throw

crossover backhand - throwing hand meets glove around knees and throw

declared backhand / V cut - throiwng hand meets glove at chest and throw

slow roller - throwing hand meets glove around thighs and throw