Nice idea, but I do not feel comfy when my car knows where it is, by GPS or so.
I am glad to have my Smart and my Insight. They're both as dumb as a slice of bread.
My Insight had 75 mpg today with A/C partially on. There's not much to improve here.
A better way: a 5 stroke or a 6 stroke engine, for example. Of course that would not be a DIY thing.