1. Avalanche. Avalanche is completely different from existing projects and experts have given Avalanche a high chance to be a big game changer for Blockchain and mainstream adoption because of interoperability, great decentralization and scalability in addition to low transaction fees. Avalanche was reviewed by SEQ and received a positive rating: https://medium.com/avalanche-hub/avalanche-consensus-the-biggest-breakthrough-since-nakamoto-66e9917fd656
2. Tezos. Tezos has been developed diligently be Tezos devs. It’s a solid, but very undervalued project. Tezos was reviewed by Blockgeeks and received a positive rating: https://blockgeeks.com/guides/what-is-tezos/
3. IOTA. IOTA has been a leading project for innovative approaches but IOTA developers had difficulties to deliever. Currently, IOTA is very undervalued and can be a very wise pick because IOTA has made huge developments recently, like IOTA Chrysalis (IOTA 1.5). IOTA description and analysis: https://medium.com/iotatangle/chrysalis-iota-1-5-phase-1-now-live-on-mainnet-958ec4a4a415
4. Cosmos. Cosmos is a promising project for a scaling blockchain platform. It wasn’t hyped yet because developers are still diligently building. However, experts have some concerns of being too centralized and Cosmos has too high inflation. Cosmos was reviewed by SEQ and received a mixed rating: https://medium.com/@CryptoSeq/cosmos-an-early-in-depth-analysis-at-the-ecosystem-of-connected-blockchains-part-one-508cd679bac5
5. Waves. Waves is an established network of a next generation Ethereum platform but has failed so far to meet expectations. However, it is a big and experienced developer team and Waves seems to be very undervalued currently.
6. Solana. Solana has started developing under Anatoly Yakovenko’s hatch just recently. It has made big progress and is shilled by prominent YouTubers and marketing figures. Anatoly Yakovenko has developed a good marketing strategy but it remains unclear, if Solana can be a top aspirant for DeFi, because concerns remained, when Anatoly Yakovenko could not respond to critics sufficiently, when he was recently confronted. Solana received an endorsement from Coinbureau: https://www.coinbureau.com/review/solana-sol/
7. Polkadot. Polkadot was invented by Gavin Wood, who developed Ethereum before. Polkadot has already established a big ecosystem and is still growing. But a high inflation, limited scalability and centralisation (dPoS) are issues for Polkadot. Polkadot was reviewed by SEQ and received a mixed rating: https://medium.com/@CryptoSeq/polkadot-an-early-in-depth-analysis-part-three-limitations-and-issues-d8b0a795a3e
8. Cardano. Cardano has already a very high Marketcap and it’s very likely an overvalued coin. Cardano was started almost 5 years ago from Charles Hoskinson, an abandoned Ethereum developer. Cardano has constantly developed but in addition to a good marketing strategy, it hasn’t achieved a working mainnet platform of contracts, like Ethereum. Release was always pushed back and promised “soon” (you know). Delays are usual for Cardano.
9. Algorand. Algorand was very promising before it started but a bad planned ICO and a huge dump after launch, where VC and rich participants sold, caused a dump from 3$ to 0.20$ and left a huge loss for many members. Wasted opportunity but developers are still building.