Mode as the master switch, because “what am I looking at — now, before, or ahead?” is the operator’s first question. A sensitivity/window dial instead of hidden config, so tuning noise-vs-latency is a first-class control. Guardrails as an explicit, visible safety toggle rather than a buried setting. And a calm, luminous dark surface where the signal glows and the chrome recedes — the opposite of a blinking wall of red.