% of EV miles might give you some guesses, but it's not going to tell you the state of the battery. They could drive gently for 1 mile on EV only every day and keep it charged at 50% and theoretically that would be 100% on battery and about as good as you could get for battery longevity...
As far as the options... I always do my best to get something fully loaded. I hate feeling like I'm missing something.
As far as individually...
-Haven't heard the "stock" stereo, but I quite like the Sony.
-The auto parking is cool but parallel parking isn't something I hardly ever need to do so it never gets used. Comes with the front parking sensors which I DO enjoy though. Other than their propensity to go off any time it rains, snow, etc and a drop of water is on them. Still don't know how they have this issue when our Toyota never does.
-The power hatch is nice mainly just because that back end sucks every bit of crud off the road and it's nice not to have to touch it, especially this time of year.
-The glass roof is also nice but mostly it's just providing some extra light unless you're in the back seat or reclining and can actually see out of it.