Since you have spare money, investing in crypto is good, but before you buy any coins, do your findings. Don't just buy any coin you see, moreover, i think you should be holding some bitcoin and ethereum also because these two have gained more acceptance.
Bitcoin and ETH is an easy choice, you cannot be rich when you only focus on this coin.
We know that when bull run starts price will accordingly rise but these two will not rise 100 times like in the past, you
have to find a very undervalued coins which volume is low right now and study it's potential, bet on them if you believe enjoy the 100 times return.