1. ETH
2. TON
3. ZRC
4. ZKsync
5. Ada
ETH would always be a great altcoin to keep in your portfolio so I choose it for #1.
For #2, another layer 1 coin could be a great addition, I think TON (or Sui, Aptos) should be on the list. I choose TON because it has real use case.
For #3,#4 I think about a Layer 2 coin for Ethereum. I choose ZRC and zkSync. zkSync is leading the Layer 2 solution now, and ZRC is new, AI-powered, and has a good community.
Another one could be ADA.
For #5, Ada is my favorite.