Everything seems good (aside from the little doodles I added in). But good could always be great. You see that little section next to the shopkeeper? It says Select an item to view details. Well.. what if it could say things like this!
Now the thing I wrote is just a bad example of some helpful descriptions in order to help out new players that try to make their own builds. It would say what the item is good at, and maybe a tiny back story on it? Either way I think it's a good idea.
Now if you want to go hardcore... you could make the descriptions change for every specific champion. Here is an example.