I think it's situational. Pick the best player for where the free kick is to be taken from. Identify which player can cover which area best and have them relentlessly practise it like Becks did. I remember watching from the Stretty when Mata saved us against Southampton with a last ditch banger from the right hand side, because he was the best option for where the ball was. Long time ago of course.
For penos, we have an embarassment of riches to choose from. Bruno, Ronaldo, Rashford, Mason, Cavani, Pogba. When Bruno eventually misses one, Ronaldo is up until he misses. Then Rashford etc. You are the penalty taker until you miss one.