There are great opportunities in crypto market and you can get life changing profits by investing in some valuable coins. A very important factor to have in mind, when thinking of a good coin to invest in, is market cap. Coins with a huge market cap usually grow slower than coins with smaller market cap. A coin with a small market has a lot of space to grow and develop. I don`t mean just select a coin with a small market cap and it gives you a lot of profit. No, these coins are sometimes really dangerous. Some coins with small market cap are weak projects and even some of them are scam and they will vanish soon.
On the contrary, if you choose a coin with a small market cap, you should do research about its infrastructure and about the project, you should read its whitepaper and you should do research about its team and many other issues. When you are sure about the project, pay attention to market cap, a good project with a small market cap is great and it may grow a lot in long run. 
Here, I introduce 5 good coins and I think they have a huge potential for future but it`s just my suggestion and I am not a financial adviser, then do your own research and decide by yourselves.
1-Crypto20
It is an index fund of top 20 coins with biggest market cap and its value is related to crypto market, when the market is bullish, it will grow a lot. Its market cap is around 70 million dollars and it is still small. It is traded mostly on Bibox. Its fund portfolio is very diverse and it is something great and promising.
2-Polymath
It has a market cap of around 120 million dollars and its not big and its total supply is 1 billion coins. It was listed on Bittrex and you this exchange wont add a coin with a great idea and good infrastructure. You can find this crypto on Upbit, Kucoin and Bittrex but mostly on Bittrex. Polymath is a platform for security tokens. Anything like stocks, bonds and so on can tokenize themselves and enter the crypto market via Polymath. It is a Canadian based company with a lot of buzz around it.
3-Achain
Its market cap is around 150 million dollars and still is not mature. Its total supply is 1 billion coins and mostly you can find it on Huobi. It is a public platform which allows users to issue tokens and create smart contracts and also decentralized applications. Its infrastructure is like NEO and Ethereum, making other cryptos from one crypto and we have seen these kinds of projects, they are usually successful. It has a long way to go to get mass adoption. They have a very beautiful website and their wallet is nice.
4-Neblio
With a market cap around 170 million dollars and its circulating supply is around 13 million which is outstanding. It is tradeable dominantly on Binance. It is a platform for enterprise applications and services and this platform is really secure. If it succeeds, the return will be lucrative.
5-Nuls
Its market cap is around 120 million dollars. It is traded on Binance predominantly and Bit-z. It is a global platform open source product which is highly customized.