The persistent week-long tournaments that are upcoming in the next beta sound interesting but without any sort of auto-balancing I don't quite yet see how the tournaments will be competitive. In fact the side that wins is kind of already determined. For example, if it happens that the better players like Regulus and Sedna disproportionately more than the other DGs and those two get assigned to the forces of light then they win, right? I think it is very unlikely that the distribution of skill level is spread evenly across all the DGs. 

Instead I would be much more excited about tournaments in which the player is auto-assigned to a side based on their rating. This rating would be derived from their past performance in games. There is plenty of work already done in this area for other games but with a little tweaking of how favor is assigned you could probably even use something as simple as the average amount of favor earned per game (after having played 10 games, a provisional rating before that). Once each player has a rating the tournament system's job is simply to assign new tournament participants to a side so as to keep the sum of ratings the same for both sides.

To go one step further I would be even more excited about auto-matchmaking of standard 2v2, 3v3, etc. games based on this rating.  

Best of luck.