More will come! Continue to build, and help your alliance to grow as well. The next major feature to be released in the game will be Alliance Wars! No details on the mechanics of this, but the developers hope to get it to beta testing in two or three months. How much development it will require after players start trying it out in beta… that’s unknown…
In the meantime there’s the monthly challenges to play with. I’m trying to put together a 3* team again to see if I can nail one of those avatars… 
You might look at this thread for more ideas:
There is a thread in the forum for top titan hits if that’s a goal for you!