If the decision is made to add Auto Zoom, please be sure to make it user selectable. I had this feature years ago on a Garmin, and didn't care for it at all. (It was user selectable on the Garmin)
If added, I would imaging it would definitely be a user option. Similar to AutoTaxi+, it has the option to enable or disable it.
Yes, please make it user selectable. I'm not a fan of auto-anything. I prefer to zoom or not when I am ready.
I already have auto-zoom. I keep the iPad zoomed out for a wide view, and the 720 zoomed in for a close view. :-) YMMV.