I wouldn’t say it’s a terrible visualization, although in general I do believe conditional 2D plots are the best way to show trends in higher dimensions. For example, here are some conditional plots for similar data (Kaggle Titanic competition) that I’ve found insightful.

http://i.imgur.com/C4uyH.png

The conditioning on Sex/Class seems to be the best way to illustrate the trends in these 4 dimensions.