one of the best low market cap coins 2021
1. Matic Network (MATIC)
2. Zilliqa (ZIL)
3. Blockstack (STX)
4. SiaCoin (SIA)
5. Docademic (MTC)
6. SelfKey (KEY)
7. Basic Attention Token (BAT)
8. Linda
I am not going to say this is not a good list or counter it in any way because everyone have something they are looking for in a coin, everyone have something they are after. However, from your list Matic being the first is a very good one as it is one of the blockchain network which can compete with BSC network if all goes well with the team and if the team sets out to implement or support things which will draw more investors and project developers in.
That's all I can pick from the list. And if I am to add, other blockchain platforms like Algo and FTM will do well on the long term. Nowadays, it looks more like blockchain platform coins are taking the lead in this space and would be wise to checkout some of them.