You know what was great about the last League?
It wasn't run by clans, and the individual player could thrive without worrying about being obliterated by large groups of players cooperating against them (both in regards of reaching milestones and being killed). Most of the ideas put forward in the blog for adding PvP/Trading make me groan and despair.
Escalation League, where clans would immediately be put ahead not only by securing a zone, but by exponential XP gains as they do so. Christ, that sounds awful. If you want to add League elements to DMM then please do so, but don't sully the one game mode where clans don't ruin everything, both by account boosting and PvP methods. I don't even necessarily have a problem with PvP, but PvP without having clans ruining it? Close to impossible, so please don't turn these into DMM 2.0.
Why not integrate group ironman into leagues instead? Have a separate high score board for individuals and people playing in groups (maybe for different sizes of groups too). That way, those wanting to trade and play with friends can do so, whilst others don't feel like they've already lost before they've started just because they're playing solo.