Stop mail replies ending up behind mail app?

I have several times ended up with half written mail replies hidden behind mail app. Some times a reply can take some times to do and im an easy distracted person that forgets to continue the mail. I had an important mail that I was so sure that i sent. But then i saw a week later that the finished mail was sitting behind the mail app. I was looking for an "always on top" option for reply windows but couldnt find any settings for that. Other than that I guess my option is to do some kind of apple script that moves them to the front. Any one else that has this problem?