In my personal opinions the alternative coins to be held
- Steem because it is first of altcoin dedicated for social media based on the blockchain and it was sucessfull more than 1.6 millions transaction per second check on here http://blocktivity.info
- EOS although it is still not available the EOS blockchain, but we know who is the developer of team, dan larimer and he is one of the founder of steemit too. So he has large of experience in the technology of blockchain.