In addition to this, you should evaluate whether you application could benefit from using the PPI peripheral to have EVENTS trigger other TASKS, in order to avoid having to wake the CPU to trigger these TASKS. Using PPI to have events trigger TASKS is especially useful for periodic things like high-frequency SAADC samplings that you would like to trigger from the TIMER or RTC peripheral, for instance. Using PPI will however require that you have the HFCLK running, which drives up your average power consumption, so you need to evaluate which is better for your application.
When it comes to optimizing your BLE power consumption it is all about choosing the right connection parameters for your application, so that you will have to use the radio for as little as possible. For instance, you should choose the largest feasible connection interval for your application (between 7.5 ms to 4000 ms), to use the radio as seldom as possible. Additionally, you could perhaps also use Slave Latency depending on your application, to further reduce the frequency of your radio usage. Lastly, you should also use the 2 M PHY, if suitable for your application, to transfer your data quicker, which in turn will use the radio shorter.
