High wing or low is a choice you will have to make for your self. There are many of either that would make a great second plane. You will no doubt get a lot of feed back on what you should acquire. Take all of the info into account along with your ideas of what type of flying you want to do, 3D, aerobatics, etc and then decide on what will suit your needs best.

If you can give us some idea of the type of flying you are interested in, you might get a better recommendation.