For long-term investment and short-term investment, I get fifty-fifty all for the risks and the profits.
The coins that I prefer for long-term investment is BTC, ETH, and coins from ready-product ICO.
The short-term investment that I prefer are some top 30 altcoins.
perhaps top 100 altcoins are better than 30. They can give your more profit than those in top 30 and they are still safe enough to invest. However, there are still risk in short term investment. If you do not need money immediately, just invest your money in those long term coins. They are better than short term investment