You take a lot of videos?I'm currently using 228.8GB of my 256GB.
Personally, I would appreciate a 512GB option. And, news flash for those that are chiming in saying there's no need for a 512GB option and Apple shouldn't do one: just because the option is there, doesn't mean you need to avail yourself of it; just choose the 256 (or lower) option.
For the rest of us, a 512GB option would be sweet.