Extra distance is a bonus. Right now, I am working more for consistency, accuracy and confidence.
I dont think that I need a new putter since I am very happy with the cheap one I have. It is an offset blade and I am fairly accurate with my straight putting stroke. I have tried out some mallet putters, but I cant tell that they improve anything for me. This mallet felt pretty good when I tried it: http://www.odysseygolf.com/Global/en-US/Products/Putters/WhiteHotXG/WhiteHotXG7Putter.html