40-50*C idle is normal. You do seem to have something wrong with your OS, 4-5% utilization is way too much in idle.
It's not BIOS flashing, that can be done through USB BIOS Flashback. It's updating the EC firmware you need to do.
You only get dual BIOS chips on Extreme/Apex, and it wouldn't have helped this situation. USB BIOS Flashback can solve any situation where dual BIOS would help, since it's damn near impossible to kill the BIOS chip.
Regarding connectors it would add cost and very few people use it. Additionally there are space constraints on the board. And the Hero is not targeting extreme overclocking specifically.
There's unfortunately no header on the board for flashing the EC, what you need is an EEPROM writer plus SOIC-8 clamp that can fit on top of this IC. Space is a bit limited as well.