Not really in response to your question (the old way had its major downsides in regards to teams being able to poach any players that came out the blue and might cause them a problem) but I would like a change to the rules for being 'Cup Tied'.
I believe in Europe the rule has changed slightly in that a player you purchase in Jan can play in Europe still, even if they played for another team in it. I think this should be the same for all competitions. Especially if the player you sign didnt play for the team, but merely made the match day squad and warmed the bench. That rule to me seems mental.