And the side effects with the system i suggested are..?
(Not saying there aren't any just i believe the dimension of trading being added to the game outweighs the possible cheating loophole..which i still believe is very slim given the restrictions I've suggested)
You need too players with the same value(or packages), wo both GM desire the one from opposing team i think at least that it rare - which lead to mostly unfair trades for one side or just waist of time looking through the avaible players.
And i miss the advantages, from a trade betwen selling a player you don't want anymore, and reinvesting that money in a player you want from avaible player from 50.000 teams instead one which should raise the likelihood that you really want him.