The first thing you should keep in mind when it comes to exchanges is its security, liquidity, elegant interface and good support system. I can suggest that one of the best cryptocurrency exchange is binance.
Binance is an exchange of cryptocurrencies that provides a platform for trading different cryptocurrencies. The exchange fee is really competitive, smooth and fast, compared to other existing major exchanges. Binance has gained a lot of popularity in a short period of time and is is because of the low and competitive exchange fees.
You have noticed correctly and the qualities you have voiced are very important, not only for beginners. On my own, I would add more reliability, since any user or trader trusts the platform with their money. I think no one wants to repeat the story of mt.Gox and the like. Also, I want to add that any beginner needs to make his own choice after looking at the various cryptocurrency exchanges. Try on your own experience several platforms and choose the one that you like best. For example, beginners can read the reviews here:
https://cryptototem.com/binance-review/. This will reduce the time spent looking for best crypto exchange and cut off the unsuitable ones at an early stage.