Is it that while using GMail so frequently you have got a feature that you want to suggest to GMail team? Dont worry, I was also searching for such link where I can try to make GMail even more better !!
Go here,
https://services.google.com/inquiry/gmail_suggest/
And tell them as much as you can.. on the right side, you can even see what all suggestions they have already made it into GMail, may be you can get your own feature in next version of GMail !!!