Very specific suggestion here; likely to be ignored but I'll suggest anyway.

I'd like to see a software option when you use the sleep timer  that gives the user the option to send sound through: A) main speakers, B) connected earphones, C) Both

When the timer is up, the sound default could be the main speakers, or maybe there is an option for that as well.

This would allow users to fall asleep wearing headphones and wake up with the alarm coming from the main speakers.

Yes, I know the backup alarm can be used to accomplish a similar action but my way let's you wake up to something other than an alarm buzzer (ie: radio, etc.)