Among the several weighting schemes used for constructing volatility indices, which ones are the best for forecasting (realized) volatility? I've constructed a volatility index for emerging markets using a (very simple) trade-weighted approach, which has 84% correlation with the VIX (2007-2012). The construction procedure is much more simple, and I'm still running my regression analysis, so I can't say yet which one has better predicting power.
After reading some articles I've seen lots of critics to the VIX methodology. Is the VIX methodology the best one or there are competitive alternatives for weighting schemes?