When my clan is challenged by another clan, I receive a notification in my site mailbox. I have to delete the e-mail, click the Clans icon, the My Clan Home button etc. Sometimes a clan challenge is deleted before I notice it,; in that case I do still have a message in my mailbox, but the challenge is gone,

Wouldn't it be much simpler and convenient if in the red bar it not only read how many games are waiting for me, but also how many clan challenges are waiting for my response?

Good point. Every so often I overlook a waiting challenge myself and don't realize that it is there until the next time I visit my own clan homepage, which actually isn't that often.