It depends on your demand and where you live.

If you are living in a country which has very high expense like developed countries, Japan, the USA., England, etc. you will need more bitcoin, 1 bitcoin is not enough.
If you are living in a developing country or a poor country, 1 bitcoin is more than enough if you don't have too high demands for luxury things in your life.

Additionally, it depends on when you retire, next year, next 8 years (2 halvings) or next 16 years (4 more halvings).