Speaking about contests, what other types of events you would like us to run in support of the launch of BitDice 5.0? Please feel free to share your thoughts in this thread.
Perhaps you can learn from other sites where their contests are participated by many active players.
You have many games to play including the 3rd party provider's games so it can be a good advantage as you can give various promotions based on the games.
For the slot games I can suggest something like deposit bonus, slot competition (to hunt for big multiplier).
All in all, as long as you can offer more regular contest, it will be better.