Apple Maps also has an "Arrive By" feature now built in.
I think one area Apple Maps could improve is discoverability. Also, I would like the see offline map support. One thing that did impress me with Apple Maps is walking directions. Both have walking directions, but I live in a rural area and Apple Maps suggested the public footpath, Google Maps takes you a 15 min detour by road. You can't actually see the path on the Apple Maps interface (you'll need something else for that like Ordnance Survey, but at least it knows there is a path. Apple Maps is still very limited with cycling directions though and only works in a few major cities right now, whereas Google Maps works everywhere. I can't speak for using either for public transport.
I do like that on Google Maps you can drag different routes out with the web app with a mouse, but while you can send the route to your phone (you can send route to phone on Apple Maps as well) it won't send the custom route you dragged out.
It is interesting to see both apps getting EV support now as well, which will be useful for those with non-Tesla EVs to help plan journeys with charging stops, because the built-in car nav either doesn't have this built in or it is bad.