So, my first idea is Mission Bonuses. Lets say there was a Mission Bonus for the Sovereign Slime mission, where you have to defeat Royal Jelly without anyone dying. Which brings me to another point, that there could be Party Bonuses, that EVERYONE is responsible for (such as no one dies, defeat the level in a minute, etc.) which will give a reward to everyone in the party. Then there is bonuses for what YOU do in the party (such as revive two party members, do the most damage, etc) and only you will get a bonus reward.
Now for my second idea, this could be something that you can do all the time, or perhaps on Earth Day. But basically, the story is "Spiral HQ is trying to lower the amount of trash in the clockworks, and there is a machine in the haven, that will allow you to put any materials (note one star materials wont give as much as two star or more) you don't want or need and put it in the machine and get crystal energy. This can go with Earth Day because it encourages recycling, and recycling gives energy, get it? Like I said, this could be a one week thing for Earth Day, or it could be all the time.
And that's all. What do you think?
Actually, there is a machine where you put in materials and get out crowns so that you can buy CE, it's called the auction house.