In general, a timer of 16-8-1 wouldn't be that bad, if we implemented a function to add time to the timer.
For example, at level 131, players receive an additional 16 minutes, and at level 211, they receive an additional 24 minutes.
The experience shows that no matter how much starting time you give, many players will use it up in the first week, and then they will still end up in a time crunch.