The concept of EC is profoundly broken in a P2P network. Such networks need DDOS protection, and need strict rules to prevent fragmentation, orphans, and reorgs.

If you want miner controlled sizes, miners should agree on a new EB by signalling the EB in a block, and taking the 50th percentile EB. Then the EB level is locked in for the next 2 weeks.

AD can work the same way it does today (it’s a placebo mostly, but whatever).