There are many features of the electrum wallet that makes it outstanding but most users who have larger amount of Bitcoin would prefer to use a more secured means to store their Bitcoin that is the hardware wallets. Being a light weight wallet, the electrum wallet gives it users control over their private keys.

There's already a topic made on the use and features of the electrum wallets you  can check it out
https://bitcointalk.org/index.php?topic=3456040.0