Import in as shot order

That was changed many versions ago (like 5 years or so). It imports using multiple threads to speed up imports considerably. You can't rely on import order therefore to order images in sequence they were shot. You need to simply sort on capture time. 

Not sure what you are talking about with last few iPhone fotos shot. They always sync for me. Might sometimes take a while while you don't see it is doing anything but they always come in.