I don't like differentiating players to under and over 26. I prefer all players develop in the same way.

Players who lose star because their team promotes and can buy higher quality players. To avoid losing a star as usual, the range of 5 star can be fixed to 20-25 for 3 seasons, and then from level 4, the range of 5 star can begin to increase as usual for 5 quality points per level. But I think many managers do not like this.