My advice is to choose several altcoins that have a low value at the moment rather than buying bitcoin which is too expensive, several other altcoins that are promising substitutes for BTC are Ethereum and the other top 3 altcoins are very promising. Many are doubtful about what is recommended on altcoins that promise long-term investment but this time I also defend some of the top altcoins.
I would combine two parts of your suggestions into one portfolio: even with fewer funds in each of the coins, a diversified portfolio, for me, is better in the long run.
No matter how stable BTC is and how much potential some alts have, it's great to have both from two worlds
But Bitcoin investing is much safer, since we invest with small amounts, investing small amounts in different places will give the best results. But no matter where you invest, it's a must to have a Bitcoin investment, because investing in Bitcoin can't fail. Success will come back to you and you can reap massive benefits, that's why I trust Bitcoin.