An interesting metric would be: what percentage of coins are in the hands of people, for whom the holding represents X% of portfolio.

This does not necessarily correlate with the weakness of hand though. If someone has near 100% in BTC, he is probably quite strong, otherwise he would not have so much. Those with over 100% are leveraged and weak. Those with quite much could be the weakest, since they sell periodically and give their coins to new entrants. Those with little should be strong, since it is not a big deal to them. On the other hand many of them are newbies and easy to scare, or are only after a quick double and then sell, or just have not developed their confidence yet.

But I see a great asset in the 930 (mBTC=USD) millionaires, me included. This number is up from only about 150 a month ago! We are in the position to continue the world-changing because money is not an issue any more. So in this sense the world-changing potential has gone up 6x when price increased only 5x. And there are many more to come in the BTC100-BTC1,000 category

I would say that the number of full-time bitcoiners is also growing fast. Where I live, the first million does not give economic freedom, but a paid-for house, and a million in the bank does.