Thou shalt not live on TimeMachine alone is a pretty fair bit of advice for all Mac users. TimeMachine is great and is certainly better than no backup at all. But it is not a total substitute for a regularly-updated clone of your drive which can be made bootable in emergency.
If you are passionate about your data you will have three safety belts: TimeMachine, a cloned local backup and cloud protection for your vital information. For local-disk backup most tech heads swear by one of two programs: Carbon Copy Cloner or SuperDuper! I have both and currently mainly use SuperDuper! Yet Carbon Copy Cloner is just as good and is free.
This review of backup software in techradar.com compares five leading applications but comes up with a surprise conclusion.