Everything in C3 is awesome.
One thing that I think could be improved is copying and pasting from other projects. I ran into this problem while trying to create a game with a small group.
Here is what I would like to see.
The ability to export event sheets and layouts.
If you could do this then you could import them to another project. Let's say I want to export 100 levels to another project, this would be a good way to do it.
I think a major roadblock to copying and pasting is when one of your projects doesn't have the right objects with the right behaviors. I would love to be able to paste an event sheet, and if I am missing an object, let's say it's MobileIAP, then a dialogue box can come up saying "Do you wish to add MobileIAP to copy this data to the project?".
This way it would be really easy to copy and paste over data.