Im disappointed too.
Well, I have a couple of realistic suggestions below as food for thoughts ... (some amateur experience with Kendo in the childhood)
* Add jagged ribs that prevent the attackers from grabbing your unbrella by bare hands. When grabbed, pulling it will cut their palm
* Make the fabric shark skin that similarly damages their palm when rubbed
* Make it actually heavy not light
* Make the grip thicker
* Make the grip longer enough for both hands
* Add a grip guard. This actually cause a stronger piercing
force because it pushes against the grip guard rather than relying on the palm friction
Cartridge distribution network is just like Amazon, right? It already exists.
> Not bad, but not a paradigm shift,
So P100D (100kWh) needs 20 cartridges, or 110kg, instead of nearly 500kg of Li-ion battery. 400kg savings.
The comment means you probably know nothing about vehicle dynamics.
Or too accustomed to dull handling of heavy pickup trucks.