mobile

Hey. I have finally made my mind, to unlock this device. It's on 5.0.2 at the moment and i think i'll leave it at S-ON for the moment. Why i am thinking of unlocking? Because the battery drains much faster than it did on kitkat and i have always been a flashaholic so it's bothering me not to flash on this one as i didn't realize that htc has the hardest ways of unlocking and flashing compared to Sony and Samsung.

1. What can i do with unlocked Bootloader and S-ON. Any specific benefit of S-Off besides locking the bootloader?
2. Do you think that 5.0.2 official is the most stable rom to date compared to the custom ones lying around, in terms of battery?
3. Any other advice overall, will be appreciated.