Hold
Bitcoin is the most secure cryptocurrency and it can be treated as a digital gold.
You will use bitcoin only to store your wealth and to send large amounts of it.
The bitcoin blockchain is slow for a reason, to resist Sybil attacks.
There will be other coins for day to day transactions.
My guess is that someday there will be a coin just for exchanging other coins at current price.
Imagine you are in a store and you own some BTC, the app on your phone syncronizes with the store owners app and shows you the exact price you have to pay at that particular moment in your current cryptocurrency for what you would like to buy.
We are years away from that, but the future looks good for blockchain adopters.