Hi,
let’s see:
Items 1 & 2 can be solved. The Wifi will be AP capable so you can attach other devices to it. The base OS is Linux and you will of course be able to configure things like iptables for firewalling.
Number 3, replacing the battery is pretty high on our priority list for the case design. We can not 100% assure this yet nor say now how this will be possible. But we definitely want that users can replace their batteries - but you may need a screw driver for doing so. But there will definitely be no parts that are glued into the case that would need to be removed before replacing the battery.
Item 4 will pretty sure not happen. We almost have no space left on the side of the device for another plug
Cheers
nicole