I think that the original idea of BBs when they designed this game was training should be profitable and better training should be more profitable (please tell me if I am wrong). I can explain how it is almost impossible to make money if you are training top class players.
I made a research for the greek community (I want to write a guide) about costs of each trainer level. I found out that an optimal weekly cost for lvl6 trainer is 65.000$ (buying price + total salaries / total weeks)! If you draft a 18yo HoF and you want to build a top class player you need more than 11 seasons of training. That means that you have to pay more than 10.000.000$ just for the trainer. If you use lvl2 gym and lvl1 training court you have to pay more than 2.300.000$ for weekly costs for maintenance plus 650.000$ to build them (half of the invested funds will be reimbursed when infrustructures are downgraded)! Total cost ~13.000.000$!
Lets say that you are training 3 players, just to balance the training cost, you have to sell each trainee for ~4.350.000$ (without counting the cost of buying these players).
Does anybody think that is possible to make a good profit that way? I am pretty sure the answer is "no". Does anybody think that is possible to sell 3 trainees over 5.000.000$ just to have a small profit? And please, dont talk about lvl7 trainer...
So, you (BBs) have something to do, to make training a top class player profitable (if this is your intension)! Give us more merchandise income for our most expensive player is (maybe) just a good start, but this is not enough. This will increase a little bit the value of these players but not enough to make training them really profitable.
Obviously, the main problem is that training is too expensive! IMO BB should encourage us to build as much as better players, not punnish us (economically). If BBs agree with that, it would be good to know, so we can make some suggestions. Otherwise, just tell me to shut up!