From a technical point of view。
The biggest risk of bitcoin is the bitcoin's price will be more down because the problem on the bitcoin's transaction, today the cost of bitcoin to sending for other wallet is very expensive and slow confirmation, it can makes the user's bitcoin goes to the another alternative coins for ignore the fees transactions, but i am sure in the future this problem will be fixed by the developers team, let's wait and see about the activation of lightning network on bitcoin's blockchain, we hope it is the best solution for bitcoin.