I think that the best thing that you can do is to sell the big man. If his skills are good, you will always be able to find a willing trainer for him, and with that money you can replace him with similar skilled, but not trainable player that will come cheaper of course.
Then focus on your local players. That can give you a huge boost on your merchandise profit, especially if they have your flag. This is what i am doing, and i have $ 150 019, when my league av is only 83k. Thats an almost 1M extra income compared to my rivals in a season...
Think the best option is to sell him.. although i like this kid v much but goes opposite for my training plan.
I also read about local NT/U21 player will boost the merchandise higher (depending on the NT performance).
and the 1M weekly income? really possiblE?