Hello,
I know you should always have your coins on a hardware wallet.
It's good that you understand this, its a mark of a good holder that you know where you keep your coins, and a hardware wallet is the right place
But for my trading position I don't want to put the coins on a hardware wallet because that would be too cumbersome but I want to distribute the coins on several exchanges.
In your opinion, what are the most secure exchanges in the world, i.e. where can I be most sure that the exchange will not go bankrupt, be hacked, etc.?
Unless you know all the risks of putting your coins in exchange I can recommend Binance, Kucoin, and OKEX, these are three of the exchanges that I'm comfortable trading my coins, but I'm more on trading on decentralize exchange, trading on the top exchange in the industry will give you peace of mind than trading on a new and unpopular exchange, it's still best to not hold your coins on exchanges for a long period of time.