Open ledger account for trading and investing with dollar is not issue. But the Matter is how can you manage this accounts to make your profits. And I also do not think the fees will be low or will be equalized because because is decentralized Currency which USA government or any other authorities can control it to be equal with the fiat currencies. Therefore, bitcoin will beat fiat currency (dollar) always.



If I will advise, it is not good to keep your bitcoins for multiple accounts  because if you forget your passwords you will be in serious danger.  Having one account for bitcoin is good as multiple if it is not better of. The total amount that can be gotten from the varieties of wallet or accounts can be gotten from one account. Example: if I have 20 BTC and I keep it in my wallet, when Bitcoin raise up I can sell it to gain profit.