I love the master league and the way it has evolved over the past few we/pes/iss games but im really hoping that when they take the next step with the ML there is a function to move clubs during a ML season.
Other clubs try to sign you up and u can check out there squad and finances before hand (much like in a champ manager game). I think it would be great to build a big strong team, full of superstars winning almost every game and totally terrorising the ML then move to a small, lowly, 3rd div club who are struggling along at the foot of the table and turn them around so that one day in seasons to come your new and old clubs could be battling it out for the top dog spot. You could in theory then continue this method (if good enough) till u have several teams in the top division all crammed full of the best players and create a real gulf between the leagues (or even within them) making it harder and harder to reach that elite status as some teams would be far stronger (although granted others weaker), it would be much harder to sign top players and in essence creating a whole new football league/ ML reality.
Also i think there should be a actual transfer market and manager vanacies listing.
I know that the ML is going in this general direction and that the focus is to include more 'football managerish options' in ML so heres hoping that these ideas rear there head in the next version of ML and help to further more increase WE/PES's gap of quailty over other football titles.

Dunno if this issue has been raised before (would be surprised if it hadn't) but i heard that programmers check this message boards for fan feedback and so fingers crossed ;)