Wow, it looks very interesting and exciting! I'm definitely going to try betting on Freebitco.in.
But I hope that you're going to add more short term events, like individual football matches, winner of certain F1 races and something similar. Because now some events have too long duration to wait. For example, betting on Bitcoin price by the end of this year or winner of F1 championship - these events will finnish only after more than half year. And weight multiplier looks like an interesting thing, but so far I haven't looked in deep how it works.