Short investment is good if you can manage it well. Check the status of your coin from time to time and check the price. But if you can handle your emotions and have some patience in trading...why not trade at long term way.
What is long term trading? You mean swing trading, like trading for a week or two? If that is what you meant, it is a good idea, but not everyone can be a good trader,.some people will just prefer to hold for short term or long. If the time is planned well, short term holding is profitable but long term holding for like 2 years can be more profitable than all. As for me, because trading is risky, Indo not always advice anyone to trade at all.