Hi.

If i'm not mistaken the ranking for the multiplayer is calculated by max score in each of the mp available? If so, it would be nice with a list of scores for each mp like missions is on campaign.
If its just a sum of all mp done, it wouldn't be a good ranking in my opinion.

I think the rankings for Campaign, Heroic, Battle rating and multi player should be split into a ranking of each class. Wizards have little or no possible to top the list due to the way scores are calculated based on damage done. With the freeze spell, it should also consider damage prevented or something like that.
I think the best way is to split the leaderboard into classes and make us fight to be the best in that class. Rewards can be the same as it is, but instead reward top 3 or 5 players in each class. Perhaps a minor reward for others in top 10.

The arena rankings, xp and paragon level can be cross classes and show off best players of any classes.

Tharexia