The tips you have listed out will really be of help to many especially newbies. I will like to add this to what you have listed.
1. Instead of multiple wallets, hardware wallet should be used because our bitcoin will be more safe and secure there.

2.whenever we want to download or update our wallet app we should make sure that we are downloading or updating from the official website for authenticity of the app.

3.while using browser extension one needs to be very watchful/ careful as they may save our information without our permission.