Variable distance until off-ramp
When on a 4, 5, or 6 lane highway, traveling at highway speeds in the left lane, in moderate or congested traffic in the left lane, I really need more than 1 mile notice of an offramp. So it'd be nice if either (a) the distance to a turn was related to speed (e.g., at 25 miles an hour, a mile notice is good, but at 65 miles an hour a three mile notice would be better) AND/OR (b) users having the ability to set the distance that they want turn-notices to be announced.
I think it would be best to have an alert according to the actual speed, as anonlion stated.
That way 1 solution fits all.
Bump alerts are fixed.
Mike Hammett commented
Suga Ride commented
Specify notification in terms of time and by user specification (some travel at speeds above 80 MPH; safely not exceeding vehicle capabilities, conditions, driver ability)