If you are going to hold for a long term, I think at least 80% in bitcoin and 20% for altcoins. Altcoins is good for short term investment and if you are going to put 20% capital for it, I believe you will not just double but triple your investment as long as you have knowledge about this kind of investment.
It's not bad to put 80% in bitcoin, but it should be entered at a lower price. for the remaining 20% is diverted to altcoins that have good potential such as ETH or BNB. Altcoins with good development such as the 2 altcoins that I mentioned will provide multiple benefits, the most important thing is that you enter at the right price and then decide to hold short or long term. For the long term is also quite good.