Quite. You might want to do MAC filtering so only known devices are allowed to connect (You can temporarily turn it off to allow a new device to connect, and add it's MAC address to the whitelist).
Regarding passwords, it's the length that matters more than anything. A minimum length should be 15 characters, longer is better.
And instead of trying to remember a long password, use a passphrase. an example might be: JackAndJillWentUpTheHill(3times)
32 characters and easy to remember, and it includes uppercase, lower case, numerics and special characters.
And, fir domestic use, it's best to write it in a notebook that you keep somewhere safe (Even Bruce Schneier recommends this.)