Thanks for bringing this up. This (the pace of change and innovation) is one of the very most important topics in Ethereum right now. I love the idea of “heterogeneous shards” and I’ve been advocating for this since I first heard about sharding. I remain strongly in favor of this, but agree that it raises some very interesting questions. Here are a few, off the top of my head:
- Is any of this possible with Eth1 or must we wait until Eth2? An idea I’ve been toying around with, which is obviously not fully formed, is, can we somehow spin up more “Etherea” i.e. chains with some value today for experimentation? The xDai chain is a great example of this. They could be sidechains, Plasma chains, “hard spoon” chains, new chains (e.g.a “Litethereum” chain with a clean ledger, which pushes the envelope on experimentation and research, a bit like a Litecoin to Ethereum’s Bitcoin), or Polkadot parachains.
- What is the minimum degree of consensus needed to achieve this or similar experimentation? Does it require a hard fork? How much can be done without a hard fork? Setting up a bridge a la xDai, for instance, does not require a fork.
- Most importantly, seconding the question you asked, it begs the question, “What is Ethereum?” The canonical “Eth2” roadmap as it stands is for “many homogenous shards.” How much can be changed without breaking protocol-level homogeneity? The shards will, for instance, potentially have differing fee markets. Could they have different governance policies? Different EIPs as you suggest? It sounds more and more like Polkadot, with a set of heterogeneous “shard” chains.