How can I improve it?

What I understanded about those minisites was quite different to others. I thought that I'm gonna make totally different designs for each minisites. But everyone says, it is for improving sites.

Improving....

How can I improve my site 1?
As I was thinking about totally different design, It is quite hard to think another different design or technique..even though it's only for improving.

Does it mean that I should remain the structure and scheme of the pages and change appearance? or improve the structure with remaining design???

............need to think about it more.