As much as i do like the game there are difficulties;

1: is the token payments for youth players which for me does not make any sense in a realistic point of view,
2:The purchase of new player needs defining, i.e. get rid of auction or at least give the ability to up the price of your bid as there appears to be no reason for the cash.
3: The injuries players sustain is completely unrealistic, 2 out with injury in one match and the fact that even though i have upgraded the medical core my players appear to be out longer than they used to be with a lesser core.
4: The card system needs a change, in a match against a friend three of my players received red cards and yet i still won the match?!? a defect no doubt.

i think you should have a youth team with all the players at different ages and when they hit 16 you can choose to give them a senior contract or not.

More needs to be based with the money you earn from sponsorships and games. i.e. paying for a player to go to a facility to recover from injury slightly quicker (out for 3 days normal, out for 2 in the facility with a payment of 1m depending on the upgrade of said facility) or to improve their ability again slightly quicker (for every 10 earned your get 1 extra)

You should also earn money from your food and parking facilities, but they are only meager earnings like 1000cash a day.