It depends, if you want massive profits like what was possible in 2017, you have to go with unknown coins. Otherwise if you just want regular profits go with BTC, ETH, LTC, etc.
I put a lot of my money recently into some unknown coins like MATIC network to make some bigger profits. These coins are more likely to go 5x-10x than BTC.
I'm not for sure that this MATIC project will give you huge profit return, we know already the sentiment of new projects today and mostly all of them turn into nothing after listing in the market exchange.
But somehow, it could be safe and seems to be profitable if we invest to those coins that have already establish in the market just like BTC, ETH and the rest of the top 20 altcoins.
Anyway, if you feel good into MATIC, then that's you decision and don't want to stop you.