I wish the GPS would display current elevation. Even the cheap portable GPS units have this feature. It's really simple to implement, too, since the GPS satellites already supply both position and elevation data - it's simply a matter of displaying it on the screen!
(Yes, I know about TeslaWinds, but when I'm driving in the mountains where I really want to know the elevation, there's usually no cellular signal so it doesn't work)
Position calculated from GPS is extremely accurate, but elevation data from GPS is extremely inaccurate. The only way to get good elevation data is from a topo map or a properly calibrated barometer. I don't know if our Teslas have access to elevation data on the maps they use for street information.
Some hand-held GPS units for hikers etc., have a built-in barometer for this reason. But they're accurate only if calibrated frequently, which can mean several times a day if the weather is changing.