Some time ago people hold bitcoin is very profitable, but for the moment it seems difficult, hold bitcoin it took patience, even look can be detrimental. I think one of the most profitable investment was the purchase of the new coins, the best time before ICO is the most appropriate moment to buy much.
I think your wrong because bitcoins prices went up quite high in last few months so whoever holding bitcoins made a very decent profits. And altcoin trading is very risky and tough to predict the prices.
And gambling should not be called as investment whether for short term or long term because these games are only for fun. Except luck nothing can help you to make money from gambling. So I don't call gambling as an investment.
Yup we are seeing too much fluctuation in bitcoin price since last 2 months. So this is not the time to buy new coins. If you hold any coins, then this is the best time to sell and make money. And yes the gambling is not an investment, it's just a fun game to kill your free time. It will give only entertainment, but if you have luck, you will get a bonus (profit).