For all that, you appear to have missed the point of the app entirely. Its designed to assist in contact tracing in the currently unlikely event of a close contact with someone infected. Its not claimed to be a perfect metric solution. Its also designed to be a form of social 'insurance' which the authorities can use to justify the opening up of the economy sooner rather than later. I reckon all your bits about battery life, Bluetooth interference etc are just elements of post-self-justification for a decision already made, not actual issues with using the app. Similar reasoning applied to driving a car, owing a dog, watching TV, flying etc would see the abandoning of all of those activities - we could all dream up 'problems' with them, most of which if viewed objectively would be nonsense.
Funnily enough, my travel and lifestyle profile seems very close to yours, yet I had no hesitation in downloading and using the app. I feel much better about myself now, knowing I'm doing something that is not just all about me.
ps iPhones at least will tell you battery consumption per app. Mine got to 1% one day, and most days its ' - '
In these days of lock-down, can you spare that much power, for a social good? Brother, can you spare a dime?