Lots of interesting stuff there - thanks :) We're using https://github.com/mwarning/meshnet-lab rather than imunes.net for network simulation currently, but will take a look.

Power usage is looking pretty positive so far; as long as we route the Matrix traffic over the routing topology rather than going full-mesh it should minimise radio usage (the main battery suck, other than screen).

For store-and-forward, honestly using P2P Nodes as intermediaries is an okay approach other than exposing metadata to them. Our plan in the longer term is to switch to loopix-style mixnets to obfuscate the store and forwarding, a la nym.

In terms of joining the network by deriving a private key from a passphrase... yup, that could be cute, although slightly terrifying in terms of the risk of weak passphrases :)

We're hoping to get the P2P network stable in the coming year (although we were also aiming for this year originally :P)