Again to make a general comment - without being in a position to reveal any details, there are a number of additions to online that we think will aid the experience, however restrictions on the players you can create aren't part of that. I personally find it great that people organising leagues can work on setting rules they think create fair play - where it makes sense we'll look at implementing some of those as match options, but it will always be difficult to be a step ahead of people seeking to find exploits to win.
I can however assure people that you can't make players that are 500cm tall.