We would like to emphasize that Tournaments should not be considered the only way to receive Units, Diamonds, or Items. Tournaments may add a bonus to all actions you perform in the game, such as fighting rivals, capturing Pantheons, attacking and defending Persian Positions, developing your Sector, etc., but they are only a nice addition. The main purpose of the aforementioned actions is to get Resources from Raids, rewards from Operations, and actively develop your Sector.
Also, Tournament rewards have always been subject to change. We regularly add some new Items, remove some old ones, change the amounts of things you get, etc. Our developers carefully calculate each Tournament reward emphasizing that rewards are a bonus, not the main point of participating in Tournaments. There are, however, rewards that can only be obtained in Tournaments. Those have a greater value since they are rare, and we do want players to participate in Tournaments to get them.