improvement to WPF xmal client screen

I am looking for someone to help me ( you should know how to write WPF/XMAL code) improve the client screen of my WPF xmal application and take it to the next level. I am using "http://metro.mahapps.com/winfx/xaml/controls". I am open for suggestions but I believe you can only change the code within the "<Grid> >/Grid> element. timeline of the project is flexible, with more than 7 days for completion. I highlighted the section you need to change.