I would appreciate a simple "keep-distance-wrt-speed" function for bumper-to-bumper situations. Where worst case scenario, you rear-end a car at relatively low speeds.
I'd happily keep control over steering in this situation and just keep my foot over the brake, though lane-keep assist would probably be handy here as well. A couple radar sensors/cameras/or lidar sensors would probably be enough for basic functionality.
Disable if the steering-wheel is turned more than X degrees - maybe 20 or 25?. Disable if speed goes over X speed - maybe 15mph? Most cruise controls require a minimum speed (like 25mph) to activate.
Trying to do full driving automation, especially in a city like Seattle, is like diving into the ocean to learn how to swim.
As cool as that sounds, I'd trust incremental automation advancements much more.