Put block limit at 1GB
Have minners send blocks using encoding  ( new 1GB block need only 4MBs to be propagated )
Requires full nodes and miners to be sitting behind >2MBPS internet connection with unlimited bandwidth.
and there you have it, bitcoin may now include 3 Million TX pre block, is that worth a little centralization?
how much centralization would this really require?
not much!

First off, the centralization would happen VERY SLOWLY, because obviously bitcoin isn't suddenly going to experience a 100,000X increase in transactions over night.

Second, once / if bitcoin does reach close to 5000TPS the requirements for miners and full node to run isn't very high, we're still taking home garde computers with home grade internet being able to handle this.

Third, ATM miners and full nodes are already somewhat centralized it's likely that these minimal requirements won't affect anyone at all. China might be affected once TX vol gose up 8X then it currently is today, chinese poeple may be required to run their full node outside of chain. so what? they will still be able to mine they won't give a shit, only you give a shit because you're scared of a Gigabyte.