I strongly believe that if some well known investors come in and buy billion dollars worth of bitcoin it could be world breaking news and the price of bitcoin would soar high to $10000, just my opinion.
I would prefer that a lot of smaller investors buy in to bitcoin. There are potential issues with a few people owning most of the bitcoins. They can manipulate the price on exchanges and could gain control with over 50% of the coins. I think it would be better all around if millions of smaller investors gradually started to invest.