Having the timer stop when you log off and continue when you log back in is probably not gonna happen, the idea is not to have an exact time in mind to know "hey i played 3 hours, im done here, time to go offline".

I do agree with having a better system than the hourly "you have been playing for x hours. Nice!"
maybe an option in the settings that allows you to decide how frequently you want to be notified for activity?

- every 10 minutes
- every 30 minutes
- every hour
- every 3 hours
- never