Add a new level of investor to the three you already have.
When I click on an article, I see some huge number of notifications and messages. I have no interest in getting such notices. The only reason I click in to Y!Finance is because my main news feed sometimes includes articles to Y!F as well as sports, weather, politics, etc... in other words, limited control of news sources. You have three levels of interest here: Professional, Heavy investor, and Light investor. But you should have a fourth: Don't care to get the notices. So to improve? Include a way to turn the alerts off.
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