I've read quite a few posts about people getting banned for their transfer market activity, many innocently, yet it is obvious that coin buying still takes place and is a scourge to the game.
Also, it's often agreed that the transfer market is necessary in order to obtain the dream players you want - you're quite unlikely to pack them.
How about a transfer market where you cannot sell but can only buy - there would be no way for coin sellers to operate and but it would eliminate trading for profit - so you'd actually have to play the game.
Idea is that every player has a fixed price for discard, the price being based on their desirability and rating so e.g. Icadi might be 200k, Higuain 500k, C.Ronaldo 4mill.
Fixed prices could update by a maximum variance of 10% every week if certain players are being discarded very often and obviously not being picked up, giving the opportunity to very savvy people to discard and then rebuy 3 weeks later for less, but also the temptation when rising prices to persuade people to part with players they might have no use for.
If you pack a player then you can keep them or discard them. If you discard then you get 75% of their value. If you discard then they become available for someone to buy at the 100% price. Only players discarded are available to buy by others.
There would be no need for tradeable or untradeable packs, they'd all react the same.
No-one would stockpile certain cards (because after buying at 100% they'd immediately have to discard for 75% back on to the market).
There would be no need to have a timer on the transfer market so less pressure on servers by those who currently refresh constantly to snipe.
The very best players would still be rare as they'd be less likely to be discarded in the first place, but you'd know your exact budget and what you need when trying to buy.
EA could even actually create sbcs based on the excess players on the market too to encourage them to sell, and to anticipate the difficulty of sbc.
Just an idea to prevent coin buying and to create a sort of transfer market based on players not wanted.