You should not invest in many different types, but should only invest in a few good top altcoins like
Ethereum, Ripple, Binance Coin,Litecoin. Here you will be safer and more stable
One of the biggest issues remain storage. While dealing with multiple altcoins, how to store all these coins can become a big headache. There are multi-coin wallets available, however my experience with them was not very pleasant. Another option is to store these coins in exchange wallets, which once again is not a safe option. If the exchange closes down, then you will lose all these coins.
It's not really advisable to store a lot of coins especially if you are not full time in crypto as it will consume most of your time if you will check their price, their development, when is the best time to sell from time to time, so I think that it is not really a good idea at all especially that there were a lot of altcoins that are not worth it to hold for long term.