Recently, I have started playing Dungeons and Dragons with close friends and family. We have 4 players, ages ranging from 12 to 25. Just now, I had a conversation with one of my colleagues over experience rewards, and he was completely in favour of experience-per-member, instead of the same experience for each member. In his opinion, awarding players for specific actions, role-playing and creative thinking is one of the most important parts of the game, since it incites players to play a character instead of a game.
Personally, I dislike this approach. I can reward players playing well with inspiration if I choose to, but more importantly, when anyone plays their character well, everyone is laughing and happy. This in itself is, as far as I'm aware, more important than experience points. Since I have a young player, I do not specifically keep track of experience anyway, I advance them all to the next level when I see fit.
Is this a good way to do this? I am afraid player-tailored experience will favour my two younger players, who are very creative and not afraid to go with their character's personality, while my older players are more hesitant to play their role. For instance, one of my older players has been following the group for the first two hours of the first session, since she didn't feel like showing herself. This is completely in-character, since she's a Druid and hasn't had much contact with people lately. However, as such, she missed out on a combat encounter and a couple of decision-making moments (inherently role playing as well).
Now I would like to add all of them are getting better, we haven't had many sessions yet but each of them had some highlights that set the mood for the rest of the game. For now, I do not see trouble with my approach, but my colleague has stirred doubt in my system. Is my method fair enough?
TL;DR: what are the pros and cons of awarding individual experience?