Melbourne

I believe they're all 10,000MaH, but I do something called wardriving/net stumbling a lot (basically making a log of the wifi networks that I see as well as their location) which uses up a lot of battery.

The first powerbank is 6 years old and probably down to about 5,000MaH of degraded capacity, the other is a newer one but doesn't charge devices super fast. The last one is a flashy one that's super new and has USB C PD, fast charging, and wireless charging which is my primary one. The other 2 are backups.

Tailor your go bags to your specific situation. I'd do 2. 1 for your immediate needs. If you had to be out for 24 hours without your car, what would you reasonably need? Try to balance things so you only take what you'd need so it's easy to carry. The other bag I would do essentials to get you by for 3 or 4 days with a car (if you have one). Changes of clothes, tinned food, any meds or toiletries you need, some cash, etc. the first go bag might not be super necessary, I keep mine purely because I often don't know that my living situation will be safe this time tomorrow. Honestly the 2nd one you probably don't need either - I just suggest it because I used to live in the country, and with bushfires and such you need to be able to grab your essentials for a few days ASAP if you need them. They're still a good idea to have in case of major floods, or an earthquake, or other natural disasters, though. But in the cities, the emergency meet points will have most of what you need anyway