Well I believe in the top coinmarketcap surely they are good for long term investment but the best altcoin to invest for me is ethereum, you should include eth in the list.
I'm fond of investing in ETH, and ETH is my favourite coin. Like every ETH lover l believe that ETH will rise up more in the near future, it will not take a long time to see it. No doubt as you mentioned investing in top altcoins is always profitable, they are absolutely superb for investing long-term. It would be better if we saw ETH include this list.
ETH has always been a favourite of many investors, but personally, I think this coin is old and certainly will not be able to rise as before because the value of Ethereum often depends on Bitcoin. I think this time you should look for new coins that are available in this market to invest because they are profitable coins. However, the risk will be higher than normal, and you may not always be able to predict the volatility of that coin.
No problem with that. If bitcoin price increase, that will be a sign for ethereum to increase. Although ethereum is an old coin, ethereum still survive and still get a good position at the exchange, and the volume is good enough for us to buy and sell and make a profit. However, if we try to look at a new coin, there will be so many new coins which can make us confuse to choose. Maybe we can select the coin which is released on 2018-2019, so the option will not be too big.