I've seen a lot of furs telling me the same story so no exception here.
And I haven't, but it probably depends on environment you're looking at. I think that there's some aversion between Furry fandom and Otherkin. Mostly because they use their views different way.
Trying to return to the topic, or semi topic theme, Is there any idea of the future expansions in terms of inversion?
For me, a nice expansion would be adapter to use serial port, which definitely is present somewhere in ARM systems
. However, it's some way converted to USB in charger block (so... what am I supposed to connect there?).
About upgrades, this would require significant costs, definitely. Although ED haven't separated PCB costs to CPU / base (this could be interesting), CPU board is quite big challenge, IMHO bigger than base (if not counting keymat), and developing expansions will require re-design of CPU board. Generally in this board most high-frequency things happen, so we must forget about pushing tracks "where they can go", but all have to be precisely set, twisted if they need to be longer, or capacitors have to be added. We don't know how exactly future CPUs will be, so we may end without some signals
yet with current pin-out it's not much probable in next few years. However, with new circuits with lack of interfaces, some interface chips to maintain compatibility with e.g. ports may have to be added in upgrade board.
So then two things emerge: Power and temperature. Power - because these chips draw some amps, and temperature because chips like to heat up. If we won't run out of power on connectors (and I've seen such thing even in commercial single-board PCs) upgrade boards would require a complete re-design of CPU PCB. This is my opinion from schematics rev. 5.1.3.