Hmm, this all depends on your taste, region, and requirements, such as many platforms support copy, and bot trading features as well, and some don't. Anyway if you count the best easy-to-use centralized trading platforms there are Binance, Bybit, Kucoin, and OKX but keep in mind these platforms require at least level 1 KYC in order use most of the features.

At the same time in the decntralized platforms you need to struggle in finding the best DEX on your desired blockchains. On the same time you need to be very conscious about the funds security while using DEX.

TBH, you can checkout maximum of the exchange service and their stats with reviews & ratings on any crypot traker like coingecko, CMC etc.