I found out about this a tad too late to weigh in but I'd like to voice my support for unrestricted leaders none the less. I love this option and use it in almost all of the games I play because of the new/interesting combinations that appear because of it.
In the games I've played there is occasionally an imbalance created, but it is never game breaking, and is always of comparable magnitude to the effects of having a good or bad starting location. I'm excited to see what we'll see in the coming game because of this.