OKX seems to be the new kid (sensation) on the block. Some of those mine-to-earn app projects are listing there. Avive listed there in December. A few days ago, Ice also did. Though there's an ongoing issue between Ice and OKX on the ground of how Ice trading was conducted there first day. Kucoin is a copy of Binance. Apart from the difference in font colour and all that, one would think both are the same platform.
Well not using OKX that much but needed to familiarize on some exchanges too. Yeah I noticed that OKX listing some mining to earn projects probably notcoin would be listed there as well when they launch. Kucoin on the other hand is same as Binance but they list frequently new projects. In terms of usage I like these three and bybit. But no one else matches Binance volume as always.