re decentralized in general

You don't have to convince me. I'm "that guy" (probably)...

https://news.ycombinator.com/item?id=10845128

...who always points out that banking, auditing, database, and eCommerce fields already achieved many of Bitcoin's goals with more efficiency and simple algorithms. I particularly love your comment about how centralized version of Bitcoin could run on a RPI. Haha. Similar to my statements here:

https://news.ycombinator.com/item?id=11184214

Note: The tangent with "contingencies" has me describing how it boils down to politics, laws, and human cooperation in blockchain model anyway. So, why not apply that to more efficient model.

re ZeroTier design

Nice constraints. I'm going to copy your comment and excellent article for now to fully read and think on technical specifics at another time when I have more time. For now, I think you might be overstating the problem with decentralization but spot on about the crowds it attracts. ;) One thing that high-assurance taught me is we can't do everything perfectly. Our trick was to reduce our security, integrity, whatever problem down to some small component (eg TCB or kernel) everything else leveraged. It looks as if you reinvented the concept to a degree by minimizing centralization as its the "trusted" part. It might help, though, to tell (or remind) you of another thing high-assurance cemented in: often easier to do untrusted computation followed by trusted verifier which is simpler than computation.

Let's apply this principle to the trusted part of a scheme minimizing centralization. Instead of all in central or decentral, we can use my concept to do a central model that produces traces of what went in and came out. This is applied to as little of the scheme as possible. Maybe just registration, authentication, IP hopping, whatever. The supernodes are run by different non-profits, people, countries, and so on according to the same rules with their own financial support (or they drop out). Each receives updates on what others or a subset of others are doing in form of in/out states. Each performs fast, simple verification of that which, for some things, is basically just storing it into an in-memory database with disk persistence in case someone asks for it. Mismatches are corrected in standard ways, automated or by people. Like with banks, each organization is responsible for its users with mutually-suspicious auditing increasing their honesty. Users get a sane default on number of and which supernodes to contact with what thresholds and such. For remailer designs, I always made sure to force cooperation in two jurisdictions hostile to each other at a minimum.

Interestingly enough, the job that Google's F1 RDBMS is doing is much harder than what I just described. It's running Adwords with a strong-consistency model. CochroachDB is trying to clone it. Rather than using them, I'm just saying strong-consistency DB model with checking over computation might be get benefits of centralized and decentralized. Last benefit is replicating and checking essentially centralized programs gives us ability to use decades of work in reliability and security engineering on the implementations. Purely P2P and decentralized models are too new for high-security despite what their proponents wish. So many problems and solutions waiting to be discovered. "Tried and true beats novel or new" is my mantra for high-confidence systems.

Note: Might try out ZeroTier as well given you seemed to have open-sourced most critical part.