While investors who risk their money in business ventures make a valuable contribution, it is no more valuable than those who show up everyday and give their time, work, and creativity to the success of that business.
Since there are many tax loopholes and political favors done for wealthy investors, they currently pay a much lower percentage of their income in taxes as Warren Buffett and President Obama have pointed out.
Therefore, there should be only one tax schedule with equal taxation for work and all kinds of investment with absolutely no special treatment for investments other than retirement ones that can't be accessed until old age.
Besides being more fair, this would increase tax revenues and go far toward reducing the deficit.