What would make it perfect? How could it better than the sites we already have?
This is my theory, let's say in trade we need a lot of analyzation to get a prediction which containing high accuracy.
let try to look at the exchange site, in there the possible thing for you to get the sentiment data for your trading just through the troll box.
My guess will be perfect if we are able to make our sentiment data about our investment.
The latest discussion, news, rumour, mathematics and technical argue. All of them are parts of the sentiment data.
Exchange site is not offering a lot of the data to make a sentiment data for your investment or speculation.