(This simply wouldn't work with the new negotiation system, but I just want to get it out there)
Players should all have a potential rating. It would specify the highest league level that the player could play in.
If there was a low star 18 yr old, you wouldn't normally buy it, unless you power train it.
It would encourage people to buy lower star players with a high potential.
Training 5* 18 yr old players to a high star level in about 2 - 3 seasons is too easy, and we never see this in real life.
A team that has age average of 19-23 isn't that realistic either.
A potential of a player depends on:
*playing time / form
*training facilities (if the training facility level is low, it would be harder to grow high-potential players)
*youth facilities (if the youth level is low, it would take more time to develop a player and bring up good potential players)
We could also talk about the inexperience that young players have, and how managers use more experienced players, but
it would be a little too realistic.
This would make youth academy players worthwhile.
Almost every soccer sim game has this, and I hope it will be implemented in the future.