I'v found a website quite similar to coinmarketcap but way more stylish and profesionnal , let me know what you guys think of it :
https://www.worldcoinindex.com/ (Cryptocoin price index and market cap - WorldCoinIndex)
I dont think there is any other alternative that is better than Coinmarketcap, it is very reliable and gives the accurate information one everything that has to do with mostly the first twenty cryptocurrencies. When it comes to the market cap, Coinmarketcap is always up to date and gives the accurate market cap information on every coin. When it comes to price rate, it is also the best too. When it comes to web design, the site is simple and can easily be accessed both on mobile and computer. So its the best, no need to search for an alternative.