The biggest players, aside from central banks, are pension funds, who manage tens or hundreds of billions. We will not be seeing them for a long long time. They move as a herd, and they haven't even really begun to move into gold in any significant way (my guess is under 2% of pension assets are in gold), much less the teeny tiny asset that is bitcoin.
They also tend to have very strict rules about diversification, and allowed % in certain types of funds. For example, a given pension isn't going to be able to invest in anything that isn't AAA rated by Moody's or S&P, that means no chance of investing in bitcoins.