I think I lost the crypto I had in my stormgain exchange account (StormGain has migrated its operation to the platform powered by YouHodler)
From now on I think I will only use exchanges that are on the top 50 or 100 by volume... or if you have other suggestions/filters when choosing an exchange?
No matter what you do, you should definitely find a safe place, if you are trading, you should use the top local exchanges. You can use Binance Exchange, Kucoin Exchange, Bybit Exchange, OKX Exchange, etc. But you have to be careful with your money, you can only keep as much money as you want to trade.
And if you want to hold for a long time, then you should definitely use a hardware wallet for that. And among the software wallets, you can also use Electrum Wallet.